Hi John
Welcome
Ok...couple of things...I am an ex-race mechanic so you will be fine working on a 928....Cam belt should be done every 4 years ish...
Electrics....lollllllllllllllllllll
EVERY 928 has electric problems....I dont think Germany had any schools for auto electricians
I seem to be replacing mine bit by bit....
When you first get a 928 with electrical problems do this...
Fuse and relay board is under a wooden panel ..under passenger side carpet..
REMOVE ALL FUSES ...AND REPLACE WITH NEW...
Then remove all relays ...clean ALL terminals and replace...
This will probably cure at least half of your electrical problems...
Any others...ask here...lol...I have probably had them as well
One other thing....its worth joining the PCGB as your local OPC (Official Porsche Centre) will then give you a 10% discount on ALL parts....it will easily repay itself within the first year...
Any more problems...just ask
All the best Brett