i was referring to the WHOLE running vehicle lol, i wouldn't pay 6k for just the engine....C5's (just the engine) around my area go for around $1,300-$2k and up to $3k with an S80 tranny. I personally wouldn't buy just the engine for that much for same reasons as you.
i was picking up B18A1's around here for $150-$200 a pop and they were good running engines, i bought 4 total and blew them all up but the last 1 because i built it for my turbo while i was blowing the others lol...but then car got stolen and chopped.