Yes, the minimum new contract you can buy through DVC is 150 points, though more points can be purchased. Figuring at $90 per point (the actual costs depends upon any offers DVC may have), then 150 points would cost you $13,500. You can finance that amount or make payments for up to 10 years. That $13,500 is a one-time cost. However, each year you will have to pay dues--maintenance fees really--that currently average out around $4 per point. Thus, a 150-point contract would require roughly $600 per year in fees. . .fees which traditionally go up slightly each year, essentially mirroring the inflation rate at last calculation.
In return for the purchase of said points, you have the ability to book your accommodations up to 11 months out from your trip date for your home resort or 7 months out for any other resort. Those 150 points go further during an off-season than during a peak season. Hypothetically, if a studio costs you 15 points a night during a non-peak time, that same studio might cost 25 points a night during a more popular time. There are numerous links on this board that shows the corresponding
point charts for a particular season at each resort.
When you purchase your points, you get the same amount of points each year to use, bank, or borrow. Using the example above, each year you would get 150 points to use for the life of the contract--current Saratoga Springs contracts expire in 2054. If you don't use all (or any) of your points for a given year, you may bank the remainder to the following year. Conversely, if you need more points in a given year than you own, then you can borrow from the next year. For example, should you skip using your points for 2006, then you could bank them to 2007, giving you a grand total of 300 points for 2007, or even 450 points if you borrowed from 2008.
What DVC does for is allow you to prepay your accommodations essentially for your lifetime and perhaps beyond. It is a hedge against inflation if you plan to visit WDW, DL, or even a resort that trades with WDW at least every other year. Most DVCers find that within 5-9 years, they would have paid as much in out of pocket accomodation expenses as it cost to buy into DVC. Buying into DVC isn't for everyone, and it shouldn't be looked upon as a true investment since it is basically a timeshare, and timeshares are notorious for being poor investments. However, unlike most other timeshares, DVC purchases tend to retain their value more and are a lot more flexible since you aren't limited to any one time during the year. I've only scratched the surface, but hopefully you have a bit better idea of what questions to ask now. Good luck!

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