I recall walking past lots of quite nice motors at an Army camp in Hereford and the surface rust on the brake discs had moved on to outright corrosion. Tyres will need replacing after a year without movement, as many a caravan owner discovers on the once-a-year outing. Park under a tree and see what mother nature can do to a car.
FWIW I would either sell, or get a friend to take care of it by moderate usage.