Here is my opinion. Keep in mind that I have nothing to try to sell you. Don't know you, so I have no reason to try to fool you.
The vast majority of cleaners are, in my opinion, mainly residential and light commercial with hose runs under 150 feet. Very seldom do they need anything more than a 36 blower. There are plenty of good, simple, propane burning TM's made today that are fairly inexpensive with a 36 blower. ( That's as low as I would go. No 33 blowers for me.)
Almost every CC I have ever met is an absolute pig when it comes to taking care of their equipment. I would NEVER purchase anything used, unless I knew the cleaner personally and knew how he kept his equipment maintained. Always buy new.
In my area, I can get a really good 18 hp, 36 blower, propane unit .. new .. for around $9500. And, I am sure where you live there is somebody close that will do the same for you. Never buy long distance if you can help it. Try to get it from a fairly local supplier that you can remain loyal to, buy your chemicals from, so he will offer you good service.
PS And don't let this place, and the people posting here, talk you into buying a bunch of extra stuff that you don't need. Speaking from experience here ...