the engine out before you get into buying one. Figure 50-90k mile range for the motor before you need a rebuild on it. Personaly I would get a rx7 with a bad motor and rebuild it myself for cheap before I bought a rx7 running but I can rebuild them. Get as much history on the rx7 if you go that route to know where the engine stands for its life span and read up on the maintaince to keep it up.
My 2 ladies and dads 350z wishing it was as sexy as my girls :)