I apologise I look at everything from my perspective and to me bigger is always best.
I don't think you need a drain jetter converted.
The Zeta @ 200 bar will be all the machine you will ever need, can you buy one for your budget, I can't remember the cost inclusive of VAT.
The Rapier is definitely affordable and is 200 bar @ 3000psi
The Hilta/Yanmars are bombproof, I have four of them, and well within budget - diesel as well.
Wait for one of the others to give you a response from their perspective.
Good luck
Rob