Hiya SL, all thats been written above is very good advice - here's my two cents.
I, like you, wish to realize the dream of a 968.
It is, imho, the best value in a used performance car on the market.
But, it is true, while the purchase price makes the car very attractive, maintaining it might be in your case (and in mine) a relatively large financial burden. All the more important to find a car that is either low milege or a higher mileage car that has all its major parts updated.
But have no doubts - this car is a high tech performance automobile and costs much more to maintain than your average domestic. The good news is, things fail much less frequently compared to domestics since the car is so well built. Ultimately, like much else in life, you get what you pay for.
Needless to say maintaining this car as a daily driver (which many do) costs more than keeping it for weekend spins and 1 or 2 week vacation tours - this is how I'll be using the car. To get to work and back, since I live and work in downtown Toronto, I'll take public transit - the cheapest way to travel. Or if you have a garage and driveway or other parking spot, consider getting a good used runabout like a Corolla and using that for daily use. Then you can get the famous bumper sticker "My other car is a Porsche!"
As for getting the money together, save save save - save as much of the initial purchase price as you can. Put the money in guaranteed investments that pay around 3-5 percent like gov't bonds or bank certificates. Be perpared to make financial sacrifices to buy the car and to maintain it downt the road.
As I said, you get what you pay for. And even though its such an overused cliche -
Purchase price of Porsche 968: $25,000. Maintenence costs over the last year: $5,000. Driving down a twisty recently paved road with no cars around on a nice sunny day?
Pricelessss.......