One of the very first things I look at with any piece of used equipment is the grease fittings and/or greased areas. Do they look like they've never been touched? If so, good chance the previous owner wasn't real big on maintenence. Bad sign. Also, look at the condition of the blades. Are they beat up with curled edges? If so, the mower might have been seing double duty as a bush hog. Not the best thing for some finish mowers. Paint can be a give-away. Cracked paint might indicate bending or flexing in places that aren't supposed to bend or flex. Look for bolts and nuts that appear to have been removed and re-installed. Has there been major repairs done lately?
If possible, have the mower put on a tractor and run it up to speed. Any odd noises? Bad vibrations? Belts slapping?
With some luck, you can even see it in action. How does it cut? If you're buying from an individual, why is it for sale?
