My biggest concern about stolen property is that Law Enforcement assumes that insurance covers it all.  I don't think any of them would want to run serial #'s all day to find out someone else bought a hot engine.  They simply don't investigate stolen goods very hard.  I knew of a person (friend of a friend) who unknowingly bought a stolen firearm at some point.  Police didn't care where he bought it or who he bought it from, but it had to be surrendered. Never followed up on it to investigate, and since the statute of limitations ran out, he didn't even get a traffic ticket (he was pulled over and was CC'ing with it at the time).  I bet the original owner never saw it either....