[fredjacksonsan]

Check for rust in the floorboards. Start it from cold and have a nice long drive. Engage the 4wd; if it's from a farm, take a drive through the fields. Make sure the trans shifts properly and everything works.

Basically, check it out as you would with any used vehicle; the rust in the floorboards is the only thing special to check that I know of.

Price? Check www.kbb.com or www.edmunds.com for general price guidelines in your area.