</font><font color="blue" class="small">( 2001 yr model 1200 hrs
R4 good rubber
2 rear remotes
Synchro Shift
Price $12,000
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Hmm... I assume it has 4wd since you said R4s.
Check the battery area for acid damage. Check that the PTO functions properly under load. Check that the 4wd operates as it should. Next, make sure the transmission works well in every gear and brakes also work properly. Get the tractor under load to make sure the clutch doesn't slip. Finally, put a heavy load on the 3PH to see how it reacts and turn the tractor off to see if or how quick the 3PH drops. I saw a similar tractor hold a round bale in the air for almost three weeks without dropping. At 1200 hours, the 3PH should be really strong. The lower lift arms should also be straight and the stabilizers in good condition.
If it's at a dealer, negotiate for a complete fluid and filter change including power steering reservoir/filter. Make sure there are no coolant leaks and that the coolant looks good and especially that the radiator has no acid damage from the battery.
The tractor is worth $12,000, especially with the rear remotes. That was a $750 option in 2001. You can offer less for the tractor, but you won't get beat up at $12,000 if the tractor looks like it has been taken care of.