New guy looking at buying a Porsche 928
 

I saw a beautiful 928 for sale in my town. I had known a little bit about the cars but decided to research them a bit, fell in love with it and here I am thinking about buying it.

The car is a 1986 Porsche 928 S with the 5.0 32 valve.

• Black/Black
• 68,000 Miles
• Sunroof/ Power everything
• Nice Borla Exhaust
• Very nice rims with 265-35-19 tires. They cost $2000 online.
• Nice Radio and Speakers
• Everything else is stock and in "new" condition
• Almost perfect condition inside and out

A dealer in my town ( South Dakota ) has it for sale. This car has been maintained very well and is a one owner car. The price they have given me is $15,000 flat. Is this a reasonable price for the car? If not what would be?

I don't really know what those cars go for. A good one -- and this sounds good: right model, 32 valve engine, etc., all apparently in good condition, etc. -- could be worth even more to a 928 fanatic. Realize if you pay this for it, even if you take really good care of it, you are unlikely to get your money out of it though. But I doubt that is a priority for you.
What probably is a priority is enjoying the car. So, I'd make sure that this car is really for you. It's gorgeous, it sounds good and has a good interior, and while not fast by modern standards it is hardly slow, either.
But realize it is a 23 year old car. Any car that age, even if well maintained, will give a lot of small problems. You could cut down on a lot of them by spending a lot ($3000-$4000) just replacing every routine wear item you could think of, right up front. Every hose, every seal that wears, shocks, bushings, etc., etc., along with repairing every thing that isn't perfect. Maybe the previous owner did those items. Maybe he didn't and is saying he did. I've learned enough over the years to suggest doing all that anyway, though.
Next, keep in mind it is a very complicated car, so there is a lot to go wrong beyond those routine things, and the mileage is about where any car starts to experience water pump failures, etc. etc. etc.
Finally, the 928 is particularly difficult to work on: a lot of things on it require removal of other things just to get to to them. Spacing is tight. It's not that easy to adjust and tune some of its systems. It's a bitch to work on actually, in many ways.
The combination of these factors means that it is unlikely to be a really enjoyable experience if you have to do the work yourself or are on any type of budget or can't live with it being in the shop for extended times. On the other hand if you are a true Porsche nut and this will be like fun car #4, then its a great car to have -- a classic and one to enjoy when and if it is up and running well.