I don't know if I agree 100% with everything so far...When purchasing used-used on a budget
a belt drive should be under $1,200
a hydro should be right around $2500+ SO THAT IS +2x the price
The hydro does have better maneuverability, decreased operator fatigue and less manhandling in general.
HOWEVER when you go used and 800-1500 hours typically...and the unit has had poor maintenance or none at all...then your buying expensive oil coated scrap metal. Pump and wheel motor replacements are very expensive.... like $550+ a piece
So I would buy a hydro every day of the week if it's very very low hours or has some service receipts.....I started with a belt drive, still have the belt drive, and it delivers the best bang for the buck. Replace each belt every year and its bombproof reliable.
Neither a hydro nor belt drive is that complicated. A jo-shmo should have no problem doing the general maintenance and could handle most repairs.
When you get into the 48-52, 60 decks the units are 1,000...and you can't "manhandle" the controls and that's where hydro is the only way to go IMHO, but in 36" and 32" deck land you can still muscle the 500# 36" deck metro around fairly easily. But constant forward to reverse to forward to do your three point turn (to keep from tearing the turf) just gets old and bangs up your knee as you hit the shifting lever...hydro you just squeeze the grips and the mower goes into true power reverse with independent steering of each wheel. I guess I forgot to mention that belt drive "reverse" is more or and assist...you still have to pull back with some force and that in general is a safety hazard and you or belt operators will learn the neutral zone and try to make turns on slightly sloped inclines so you don't have to "pull" for reverse.