[19psi]

If you're not a hands on kind of car guy, the 928 probably isn't the car for you. While it's a standard internal combustion engine that's well thought out and easy to work on, it has some quirks that the average shop will not know or care about. The average mechanic has worked on hundreds of Mustangs and Toyota Camrys, but most likely has never seen a 928 engine in person.

For instance, you need a special tool to properly adjust the timing belt tension and the instructions need to be followed closely. If the car is an automatic, there is the thrust bearing failure issue. Once a year you should release tension on the flex-plate and check free play measurements. If the original owner let the timing belt go until it snapped and killed all the valves, odds are the tension has never been released from the flex-plate. If there is too much pressure on the thrust bearing, it grinds itself to death and destroys the engine. This is a Porsche design flaw and not part of general maintenance listed in any manual.

When something breaks, you will not be going to NAPA or AutoZone to pick up a replacement part. We have several dedicated parts suppliers that make this hobby worth it and their knowledge is incredible. Downside is that you're going to wait a few days for your parts to be delivered. Most parts are priced reasonable and they work hard at reproducing or finding alternatives for NLA parts. The more expensive parts will be on par with going to a Ford dealer to buy a part for a current model Ford. They aren't AutoZone cheap but they also aren't Ferrari or Lamborghini expensive.

The money pit guys are those who claim a timing belt costs $5,000 to replace because they take their car to a place that rapes them senseless. Reality is that it's an afternoon job that's easier to do than on many 4 cylinder cars.
I'd really recommend attending a 928 gathering in your area. It would be a fun learning experience before jumping into any 928.