Buy on Shell quality not engine, rust is your enemy and engines are cheap and easy to replace or swap.
I would look for a late plate run out model with all added extra's thrown in, more 8 valves out there but still a few good 16v cars.
If the sills are rusty in the door shut or have crushed jacking points then walk away, unless you have money to have it done properly.
Don't buy a Mk3 without getting under it or having a look behind the sill trims, no matter how good the rest of it looks
