I bought an engine off of CL a while back from a local guy that goes by Mopar Brian (go figure). He buys and sells a lot of Mopar stuff locally. He was selling a used 360 crate engine and I was looking for something temporary until I could get my stroker built. He advertised it as a full roller motor (whatever that means) with very low miles. It supposedly came out of a buddy's car that went big block.
When I got over there, I asked did he mind if we popped a valve cover to see what rockers it had on there. He didn't mind but sure changed his story when we found stock rockers in place. He knocked $100 off of the $500 he wanted and even wrote on the receipt that he guaranteed it to be a "kick *** little hot rod motor". When we got it home we blew it apart just to check things over. The timing chain was so loose it was about to slip, the M1 intake was rotten away from the inside and hidden by epoxy, and there was a layer of sludge in the bottom of the pan 1/4" thick. When I called him back and told him about what I had found, he got all defensive and wanted to yell and scream at me. Just like when I catch one of my children doing something wrong, the first thing they do is get mad to deflect from the fact that they screwed up.
Long story, short, I sold EVERYTHING but the roller block and made all of my money back and then some, and basically got a 1990 360 LA roller block for free. My point is, trust no one until you see it with your own eyes.