Before buying EP3 check front suspension components, as these wear out pretty quickly (bushings, tie rod ends, ball joint and sway bar end links)
Check for signs of wear on your clutch, standard one takes a hammering and arent really that good tbh.
Engine mounts too are worth checking out.
Just general checks for mechanical issues as you would for any other used car really.

As for cons of owning one, it is a pain to park, turning circle is terrible and the red Recaro's are a pain to clean.
IMO try to find a facelift model.

Most importantly K series is cray.