The car looks ok from what can be seen but you need to check it all over, the only suds & sprints in this country to have survived this far have either been cherished from new, low mileage, summer use only, stored for a long period of time, or spent a large period of their lives in a better climate. I have a series 1 Ti (58K from new) & a trofeo sprint LHD (spent 14 years in a dry part of Italy & stored for quite a few years in the UK & france). If either of these cars had lead a normal life in the UK in the 1970's & 80's neither would be here today!!
The car you are interested in seems to have good panel gaps - wings to bonnet, good n/s door panel gaps to wings (but could be not so good on inspection!!). Please remember that when these cars were made there were no computers used in production processes so to speak of so the panel gaps will not always be to modern standards as panels and press tools varied. The photos you see on 1970's car brochures are of the best cars available on the day of the photo shoot!!! The interior on the car looks very original, seats, door cards, and original carpet. You need to check front inner wings for plating for previous mot repairs, beneath the front screen, rear tailgate, rear wheel arches, inner / outer sills, rear suspension areas, boot floor, door bottoms, area around the fuel filler cap etc. The car will have had repair work most probably, what matters is the standard of the work really and there's not large areas of filler, the paint on the car looks fresh so needs a good looking at. The wheels look like early Lancia beta alloys, I had these on an early black alfetta gtv that I once owned (CYK963V - anyone know of it today?!), I changed them back for the original GTV alloys in the end but its all down to personal preference really. Quite a few italian cars have early beta wheels on them, maybe because betas rotted away faster than alfas in the 70's and after a few years all that would be left would be the alloys.
If the car looks on inspection to be good or better than then the price I would say is fine, maintenance is always 'ongoing' with an old car & much more than any modern car, mechanics on these cars are easy, its always the bodywork. Hopefully other people will reply to you as well as i'm no expert, only what I have picked up and learnt over the years.