This is a little long but I hope you read it all.
No matter what you decide to buy....one thing many people overlook in many different businesses is actually having a business plan. If you write a realistic, thorough business plan....there is almost no way it shouldn't work. If it doesn't work then you either wrote the plan the wrong way or you didn't execute it properly. Writing the plan isn't something you sit down and do over the weekend. It takes time. You do a feasibility study first to see if it's even worth writing the plan.
I have a good friend who is a great business consultant. I have the good fortune to be able to pick his brain whenever I want. Our line of work is a little different because almost all of us start out basically the same way. But contrary to what many people think, you don't really want to just plan on this next piece of equipment and then figure out how you will pay for it. It's the opposite. Visualize what you really want your business to grow into. What does that look like? Do you have 5 crews, fire wood sales, chip sales, maybe a landscaping crew? Whatever it is....start there and figure out the logistics. How does it work? How much does it cost to run? Etc. Then you work backwards from there to where you are now. Eventually, you get to the step you're currently thinking about and the answer is right in front of you in the math. It's like an upside down pyramid. But you start all the way at the top and work back to the single piece at the bottom of the triangle. This gives you a solid road map and a timetable to get to where you want to be.
Another thing....when (if) you write the business plan, don't worry about how you will get the money to pay for it right away. That part comes much later. Find out how much you need and figure out how the whole thing functions. When you have a good business plan, getting the money to pay for it is the easiest part. Everybody loves a winner. A few years ago, I was reading a story about a guy who wanted to start a cement sales/distribution company. He got the investments to start out with 12-15 brand new Mack cement trucks and the operating capital to get off the ground. I bet it was over $5 million up front...maybe more and he got it because he did exactly what I just described. He had the right plan. The likelihood of him starting with one old truck and ever making it to that level is very, very low.