I owned a 1997 Phase 1 Alfa GTV a while back, it was a 2 Litre Twinspark and went like a dream,
Cambelt intervals on the Twinspark engines mate are EVERY 36,000 miles / 3 Years, whichever comes first. So make sure it's had one within the last few years otherwise that's £400 straight out your pocket the instant you get it home.
Airbag warning lights come on as a past time, as the sensor is positioned under the seat it sometimes can get Jimmy'd and knocked out of sync, simple enough to sort that out so no biggy there.
Other issues are the suspension, gearbox, and clutch. Make sure the suspension feels tight and doesn't knock or feel too wallowy, throw the steering wheel side to side to ensure this isn't the case.
My GTV would crunch going into 3rd gear when cold, make sure the gears flow smoothly, mine had 136K on the clock though, lower mileaged examples shouldn't have this issue.
Make sure the clutch feels fine and there's no slipping as well.
Just basic stuff really.
Get one with FSH, in great condition, with decent mileage and you won't go wrong, in the world of Alfa you can always get a cheap car that can end up costing thousands, it's better to fork out a bit more wedge and get a better example.