OK, I'll vote.
I buy new, both cars and boats. And make sure they last a long time. That way I get over the minor teething problems under warranty and know what's going on with that particular machine. That goes for Toyota and C-Dory as well as Catalina sailboats. Journey On is now 5 years old, and some stuff is screwing up (bilge pump, trim tabs, autopilot,) but at least I know the major thing are OK: engine, hull, Judy.
Every time I went and looked at used stuff, the boats/cars available were not worth the difference in money. Boats depreciate slower that anything else I've owned, less real estate.
When we went to but our last sailboat, I heard the statement "well, if you buy new, you don't have to fix all the problems from the factory." That was for a 10 yr old boat.
And of course, there's my only second hand truck: 50 yrs old and still running. Of course it was given to me when it was almost new (19 yrs old.)
Boris