As far as an amalgamation of three microcaps, and we are looking for more. With the businesses that we have right now today, our trailing adjusted EBITDA is $12 million. We see this growing to $40 million by the end of the decade, and that's just from organic growth. We've been investing for growth, and we think we're right on the cusp of starting to show what we can do. We also have significant NOLs. The EBITDA that we generate, a high percentage will be converted into free cash flow. What do we do with that free cash flow? Number one is we invest for organic growth. We also are looking for acquisitions, and we're also consistent and aggressive repurchasers of our own stock and that we expect that to continue. We have very high insider ownership.
Both the management and the board own a significant amount of stock. I own a significant amount of stock, and we are regular buyers of our stock as insiders. Just a little more financial detail, showing our vision over the next, say, four years. If our projections pan out, we will double revenue, double gross profit, and really get the leverage of growth will show up on our bottom-line results. We're targeting adjusted EBITDA of $40 million and earnings per share of $10 a share. We think if we get even close to those goals, we're on a path to getting added to the Russell 2000 and escaping out of microcap purgatory. We'll really have the flywheel going at that point, in that we'll be better able to do acquisitions, which will further enable our growth.
Just a little more detail on the businesses that we have today. There are some commonalities in the characteristics between these businesses. One business that we're in is building solutions. The theme here is factory-built construction. Even though anything construction has some cyclicality to it, we think there's a secular growth theme in these businesses where over time, factory-built will gain share from anything that is built on-site. We have a business services division. Business services is an area that we like. We like B2B as a characteristic. What we do here is a variety of services for Fortune 500 companies. We also have an energy services business that provides mission-critical drilling equipment for rental for any kind of well that might need to be drilled. Traditionally, this was oil and gas, but also does geothermal, hydrogen, mining, water.
Our tools can be used for any kind of drilling. Lastly, we have an investments division, and we believe we have over $20 million of assets. We estimate $20 million-$30 million of assets here that will get converted to cash over time, and this is a collection of investments in a private company, real estate, and we also have a public equity portfolio of potential acquisition targets, and I'll get into that a little bit later. You could think of Star and our structure as somewhat like a private equity fund. There are also some critical differences, but similar to the private equity concept, we have platform companies, and the role of Star is to help those platform companies grow.
We're looking for bolt-on acquisitions, adjacent acquisitions, and the idea is that any business we're in, we want it to get to critical mass, which we would define as $100 million in revenue and at least $10 million of EBITDA. At that point, we're starting to realize economies of scale. We're starting to build something interesting. If we do ever reach the point where a business is more valuable to somebody else than it is to us, we are open-minded to selling it, monetizing a piece of it, spinning it off. It's all about creating value for shareholders. As I've mentioned, we think this structure that we've built, this platform that we've built, will launch us into the Russell 2000 and allow us to escape from microcap purgatory. A little further on the private equity concept, Star corporate has 12 people.
We take care of all of the functions of being a public company, but we also have an internal M&A team that has built up quite a bit of experience doing acquisitions. This division of labor that we have between what the corporate team does and what the operating companies does, it really frees up people to do their highest and best use. We have five companies that we own 100% of. There's 1,500 employees at those companies, our structure really allows those operating companies to focus on their business, growing their business, looking for bolt-on acquisition targets without all of the distractions of being a public company. We've invested in micro caps for some time. I have a lot of experience in that sector, the management teams are spread very thin.
What struck me about investing in the sector and serving on the boards of some of the companies in the sector is how much time the management teams have to spend on public company functions that don't really help the business, the operating business that they're in. Our structure allows for a really elegant division of labor in that way, and is similar to what you would see with a private equity firm and that private equity firm's portfolio of companies. I won't go through every line of this, but just a snapshot on how we operate. We do have some debt down at the operating company level that's currently about $12.4 million, and cash is somewhat at the operating companies, but we try to keep the cash up at the corporate level so that we can allocate it to its highest and best use.
Our net debt is small. It's $2.1 million at the end of the most recent quarter. With our cash on hand and with the credit lines that we have set up on our operating companies, we think we have plenty of firepower to pursue the acquisitions that we're going after. This slide shows the book value of our real estate, public investments and private investments, and you can see that that totals about $22 million. The market value for some of these items, particularly the private investments, could very well be higher than that. This is the $20 million-$30 million of, let's just call it other assets that we think will get converted to cash over time. As I mentioned, we have preferred stock, outstanding common stock.
A lot of different ways to look at market cap enterprise value, and happy to take questions on that. How did we get here? I mentioned that Star is a collection of three micro caps. The most recent merger that we completed was between the old Star operating companies and Hudson. The Business Services and the NOLs came from the Hudson side, and we kept the Star name, and this last merger was completed in August. Since that time, we've been more focused on offense, more focused on looking for acquisitions. There's several things that we're working on, both in public company land and also with private companies. Just talking about the in-house M&A capability that we believe we've developed, similar to what one would see at a small PE fund.
We had a healthcare business that was more valuable to someone else, and we merged that with a very similar healthcare business that was owned by a PE fund. We merged the two businesses together. Their business was a little bit larger than ours, but our management team was the more experienced management team, and our management team was the surviving management team. Our management team was really thrilled with that transaction. We still have a stake in that company. It's called Catalyst MedTech. It's majority owned by a PE fund. At some point, they're going to sell, and our equity and seller note will get converted to cash. We've done some acquisitions. The first two here, Big Lake Lumber, Timber Technologies, were in our building solutions division. Alliance Drilling Tools was our energy services division.
I mentioned that we have a portfolio of other micro caps that could be acquisition targets for Star or acquisition targets for somebody else. We strongly believe of the micro caps that are interesting, a lot of them just shouldn't be public companies. They're not thriving as public companies. It's not the best way to maximize value for shareholders, being a small micro cap for 10 years or 20 years. Two different times, we've taken a position in another micro cap. It's typically 5%-10%, and we'll start to engage with the target about selling themselves, merging with Star. Both instances in the past that we've done this, the company has ultimately hired an investment banking firm and ended up getting sold. In one case, in Servotronics, we made four times our money. It was an incredible return on investment.
We have a third one that is TBD. The company is called GEE Group. The ticker symbol is JOB. We have a position in that. We've been public on that. Similar to these other two, they've hired an investment bank to sell themselves, and we may participate in that process, or we may get outbid, and if we get outbid, we'll make money on our investment and go on to the next one. We'll see how that one plays out. I've mentioned our goals. We're pursuing organic growth goals. The businesses we're in, we think will grow revenue at least 10% a year from here. We think we'll generate $40 million of EBITDA by the end of the decade. We're also pursuing acquisitions. As I've mentioned, we think our common stock is cheap.
We really don't want to issue common stock for acquisitions at anywhere close to the current price. We've been buyers of our common stock. We would rather use preferred stock that is trading around par for acquisitions. As I've mentioned, we will invest in other microcaps that could be acquisition targets for us. When we think about the opportunity set, this is where things get exciting. I've talked about microcaps that shouldn't be public. We've actually done some research on this, and there are 3,000 public companies in the U.S. where EBITDA is less than $30 million. Probably a lot of these should not be public companies over the long term. There's a select number, maybe 5% of them, where it could be a fit for us.
In addition to that, there are literally millions of private companies out there where they don't really have a succession plan, they don't have a retirement plan, and we've already had several instances where we have bought them and selling to Star has been the retirement plan, and that is a win-win type of situation. What are those characteristics that we're looking for in a business that we would acquire, whether it's a public company or a private company? There are some common characteristics in our existing businesses and in the acquisition targets that we're looking at. Because we're small, we don't want to do anything that requires a lot of capital. We'll leave that to the big boys. We like businesses that are asset light, capital light, have low maintenance CapEx.
We look for industries that are growing and businesses where we think there are some interesting organic growth possibilities within a growing industry. If it's a fragmented market where there's a lot of bolt-on acquisition targets, that's also a plus. I've already mentioned that we have a preference for B2B over B2C. We absolutely need an excellent local operating management team with our model. If you think about the expertise that we have at Star, it's really capital allocation and strategy and our structure. We are not going to be operating a business from our Connecticut headquarters. We need really good local operators for our business model to work. We like businesses with low obsolescence risk. The verticals that we're in now are building solutions. Anything that is related to factory-built housing, prefab are things that could be interesting to us.
Business services, staffing, that's a business we're in. Energy industrial services. Those are all sectors that we're in which we would like to get bigger. Other things that could be a fit, anything that's industrials, manufacturing, materials could be interesting, could be a fit for us, as well as transportation and logistics. The rest of these slides go into a little more detail on our current businesses and how we're going to achieve the growth that we think we're going to deliver. If any of you have some questions, you can ask that at the end or contact us separately, and happy to do a deeper dive on our operating companies. In our building solutions division, we currently are at a revenue rate of around $80 million, maybe a little bit less than that on a TTM basis.
We see these revenues growing to $100 million. We think that'll generate gross profit of $25 million and adjusted EBITDA of $15 million. Business services division is at a trough right now, step number one is to get this business back to $100 million of gross profit, $20 million of EBITDA. It's a global platform that we've built, we think incremental revenue will deliver a 30% EBITDA margin. If we're able to double revenue over time, we think that that margin will go from 20%- 25% with 30% incrementals. Our tool rental business we see growing to $10 million over time. Adding those up is how we get to $40 million in adjusted EBITDA. We have some pretty specific guidance here by division. With that, Joe, we'll turn it over to questions.
Thanks, Jeff. Great, insightful presentation. Since you mentioned it, let's start off with the GEE Group acquisition proposal. You guys made an announcement today. Can you provide some additional detail as to how GEE would fit into Star? How you see this opportunity playing out?
Sure. In our business services division we have a business that 2025 did $72 million of gross profit. It has a bright outlook. What our existing business does is services to Fortune 500 companies. It's basically an outsourcing of anything related to talent. Part of this business is like what a recruitment agency would do, part of it is like what a staffing firm would do, and part of it is what an HR department would do. Bigger companies, Fortune 500 companies that hire thousands of people a year can save a lot of money by outsourcing all of those functions to us. Staffing to us is a natural adjacent business to the business we're already in, particularly if it's professional staffing, white-collar staffing. GEE Group is a fit with the business we're already in.
We think when we look at GEE Group Inc., we believe there are millions of dollars of costs that can be taken out if it was no longer a public company. Right on day one, there's the duplication cost that can be eliminated with putting any two public companies together. That's got to be $2 million-$3 million, and by putting this business inside of Star, we think there would be further cost cuts. It's a business that we look at, and we think those same revenue would be just a lot more profitable as part of Star than as a standalone public micro cap. On top of it, there could be some cross-selling opportunities between our clients and their clients. It's very hard to quantify that, and we would certainly never buy something on that hope, but we think that exists.
We just think the employees and clients of GEE Group would thrive better inside of a larger company, being part of a larger platform, whether it's Star or whether it's something else. We're not going to overpay. We're not going to get into a crazy bidding war. We're stockholders. We feel like we can win either way.
Great. Let's stick with Hudson for a moment. Can you talk about some of the other investments you're making in the business? I know you've got some AI-related products that you've been rolling out. I saw today a report from ADP saying the labor markets are showing sustained momentum, at least here in the U.S. We'll presume that would be a positive for the business. Maybe you could talk a little bit more about some of those new products that you're rolling out.
Sure. Before we get to that, just a little bit of context. When this business became part of what is now Star, when we started getting involved in it, we saw an opportunity to really increase the organic growth, starting in 2018 when we got involved, and we had really good organic growth for the first five years. We grew gross profit from $40 million- $100 million, and that was through investing in sales and marketing predominantly. COVID happened, and there was a big hiring boom coming out of COVID, and we've been living with the aftermath of that for the past few years. It was a very high turnover, high attrition. A lot of people were leaving their job, going to a different job. The whole nature of work changed dramatically with so many jobs shifting to remote or partially remote.
There was just a lot of movement going on. We brought in a really strong management team to start running this business in late 2023, and since that time, we decided to use the downturn to our advantage. We started investing heavily in tech and upgrading, upskilling the sales, marketing, and management of this business. We think those investments we've been making are really poised to take off. On the AI front, if you think about anything related to talent assessment, talent management, talent procurement, AI is the number one thing that our clients want to talk about. How is AI going to affect my talent needs? How can we use AI to maximize our talent?
We have developed, in conjunction with some technology companies, some tools for our clients to use, and it's being incorporated into our service offering, and we're starting to win business because of that. I would argue in any kind of business services industry, there's going to be winners and losers, and the winners are going to be ones who use AI to their advantage, help clients use AI, and it just deepens relationships with clients to be that trusted partner that's helping them navigate all the changes going on in the world. Companies that haven't figured out how to use AI with their service offering, we think are going to lose share over time. We've invested in it. We have a phenomenal team.
We've gotten really great reviews from our clients when we've done demos of the AI tools that we've developed, and it's helping us win business. We're very excited about our offering and about how that's going to lead to future growth in revenue and increase our profitability.
Great. You talked about $20 million-$30 million of non-cash flowing assets. Can you talk about your efforts to monetize those?
Sure. One big item here is the real estate. What we have done historically is either sell real estate that we're not using or do a sale-leaseback transaction. We have done those, I'll put it in multiple parlance, where we can sell real estate, let's call it at 12x EBITDA, roughly 11x, 12x, 13x EBITDA is roughly the multiple that we're getting for the real estate. Given that our trading multiple is much lower than that, we feel like it's very accretive to sell real estate at, say, 12x EBITDA and use that to buy back our stock, which has got a much lower multiple than that. We have two pieces of real estate remaining that are worth $8 million-$10 million. $8 million is a book value number.
$10 million or maybe more would be an appraisal kind of a number, an estimated market value kind of a number. Let's call that $8 million-$10 million. The rest of it comes from what you see on this slide. Mainly comes from Catalyst MedTech. We have a seller note that is on our books for $8.5 million. The book value plus the PIK interest is really $9.2 million. We did take, after we did the transaction, the PE firm marks this position to market every quarter. There were some hiccups after the merger happened. EBITDA declined temporarily, and so the PE firm marked down the value of Catalyst MedTech. We just followed the PE firm, and when they marked it down, we marked it down, mainly the equity, but also a little bit the seller note.
That business has now recovered, and the PE firm has now marked it back up, but we are not allowed to do that under GAAP accounting. We're in the unusual and uncomfortable position of having a different mark on our books than what the PE firm has on its books for the exact same investment. It's just one of the vagaries of GAAP accounting. If you add up where the PE firm has these two investments marked, the equity and the seller note, you can see from this slide it would total $15.2 million. As of March 31st, our public equity portfolio is $4 million.
Great.
That easily gets to $20 million. We think about it as $20, $30 million of potential items that will get converted to cash over time.
Great. Well, Jeff, we've come to the end of our allotted time. We covered a lot of ground today and got significant insight into what Star Equity does, its markets, and opportunities. We appreciate you taking the time to participate in our conference, and we wish you and the company the best in the future. Thanks again.
Thank you, Joe.