Suds and sprints are mechanically identical up to 1984, when the sprint changed over to 33 suspension, etc, so no difference there really. The later sprints with outboard front brakes and drums at the back are maybe slightly easier DIY, but overall they're relatively simple cars now, based on a 40 year old design. Cam belts (2 of them) but pretty reliable, and cheap and easy to change - belts are about NZ$20 each here and it's maybe an hour or so to change. Often the tensioners are fine. 60k km interval.
Given even the newest sprints are getting on a bit, the most important thing when buying is condition, most importantly rust. I'd say your best option is to just buy the very best you can find, but that could be expensive with NZ10k changing hands here for good low mileage cars.