I see it now- 2 wheel drive, still offer you or him $500, it will need gone through pretty deep. Clutch worn/wear, Hydro fluids take a couple of cycles and changes to clean out the old, particularly if it has gotten ANY water in it- which means rust INSIDE. Gears, bearings, seals, Starter, alternator, and of course injector pump. Tires that sit might hurt your feelings after you have gone through the mechanicals only to have them dryrotted and not holding air, and or rims with rust you can't see. Not super money pits if you are handy at doing your own work, but parts add up. OTOH. If you do the work and source used or salvaged parts where you can instead of brand new, you could wind up with a nice machine. IF you do some internet searching for that tractor with a FEL already on it and running- it may only cost you around 3-3500, for comparison, and may only need a clutch in its future- or tires..... You might wind up with 3k in that one if you found a FEL from a salvage yard. Maybe, maybe more.
I would take that machine and couple it to a bushhog and never take it off, for my use. I have an ASV RC30 CTL, and a Mitsubishi 372D 4wd (no FEL) and my 15 hp Mits is currenlty only on BH duty. I'd let my Mits pull a box blade with ripper teeth (and it uncouple from the 3pt quickly, and haul a trailer the rest of its life)
These Sub and Compact Ag tractors are prevalent and can do alot of work for their size, but I would always be preferring a 4wd unit- PARTICULARLY if its the only tractor or tool of its kind I owned.