When I was buying, I was told if you are going to buy a second hand machine, a 21 lpm 200 bar so to say, with lances an hoses, not to pay more than 800 as it's then on the boundary of buying new, so as Serg says it may be worth picking one up for 750 ish and being able to sell on for 500 ish if you do decide to buy a new one, that way there's not a massive out lay and jobs can then be done, money starts coming and equipment can then be renewed.
I think no matter what, your going to need a tank to draw from so you will need something that hold about 300L ( this won't last long so need to be feeding it ) I use 650 and can empty a full tank in just over an hour if am not feeding it, so the bigger the better really, just depends on van size,
Again the info am given is not to buy a second hand fsc as on another post there tonight it's gone pop just like a second hand machine can, ( not to put a dampner on the idea ), and am sure I read about someone buying a fsc the other day, it would not work with his machine or something so beware and check first before spending
