Looks tidy enough with the very limited mods I would guess about 175bhp. Ditch the DV and it will run so much better.

Rust rust and more rust are the main things. Check panel alignment. Smoke on cold startup is usually valve stems and is a piss easy job to sort yourself. Check for knocks from the engine and make sure the LSD is still present as a lot of people kill the original box and stick an XR3i one in to save a few quid. Make sure the car drives and brakes in a straight line and make sure teh ABS works (if fitted) although you may well decide to remove it as it's shit anyway.

Don't buy it with the heart buy it with your head. I've seen people part with cash for what has essentially been a polished turd. And I viewed several Fiesta Turbo's that were the same. Two of the cars I viewed were eventually sold and surprise surprise they are back up for sale again.