Surprisingly the 928 was very easy on the maintenance budget. Brake pads which I did myself. Adjustment on headlights, recharge the air conditioner. We had the car for about 4 years and just had normal oil, filter, and other normal maintenance.
The 911 SC is not driven much is a garage queen but cost me over a grand on a new shift linkage, oil change, filter, new O2 sensor, and fluid top-ups. And I supplied the parts but very few Porsche mechanics still work on air-cooled engines. My guy was a Porsche/VW guy and while the price seems high, the linkage had broken and he had not only to replace some but do some welding to keep me from spending a few more thousand dollars on further transmission parts. The parts for the 911sc are out of sight at the dealership so I order from Pelican Parts.
I have tried to keep it very good. I have the original seats, a second leather set of seats, two original Targa Tops, the original tool kit, the original manual and a service guide with original cover. Since this is a US Model, it came in with an 85mph speedo which has been changed to 180mph speedo but I still have the original speedo.