There's dents...and then there's DENTS.
A smashed in side, front end or rear may present problems with the frame or unibody.
Mostly if it's just dents, it cosmetic. If you don't mind a few dents, buy it. I wouldn't touch it myself. I bought mine, rust free (California) with 2 small pings in the bed and a broken header panel...other than that, the body was clean as a whistle. It cost me $400, delivered. It wasn't running, but after a weekend of tinkering with it I was back on the road
1990 XJ Laredo - White & Chrome
1988 MJ Pioneer - Metallic Green and Black