Hi snoopy, happy to field comments about people's opinion of the price.
I don't think this car has "engine damage". I've been using it for years without issue and it performs really well, it just blows smoke. As listed in the ad, compression seems all within spec and it happily did a long distance trip over Christmas with no issues.
After looking at the asking price of other 850R's (many of which also seem to have minor issues or extensive modification to engine internals of unknown quality), looking at their condition, whether they are a sedan/wagon and whether they are manual or the much more common auto, I don't think this one is priced that unrealistically. In fact the asking price is less than other 850Rs I've seen for sale, many of which are automatic sedans.
I'm negotiable on price, but I don't really have any reason to think this has a damaged engine. Smoking after idling seems to be a pretty common issue people have with these cars, and I've tried to be as clear and honest as I can about the good/bad with this one.