You might be better off over on the DVC boards, but I'll try to answer your question here. In '03, we bought 150 pts at BWV...DVC. You buy these points and then use them however you wish for your vacation. Different times of the year have different points required to stay...as well as different size villas. You can have a studio, one-bedroom, two-bedroom or a grand villa. Depending on what type villa you need, and the time of year you go it will cost varying amounts of points. More points are needed on Fri/Sat nights also. So, you buy these points for a set amount...might be in the $93 per point range now, maybe higher. You can finance throught Disney. You will pay maint. fees/dues each year (or monthly..your choice).
Now, is it cheaper? Probably not. We normally took a trip to WDW every 18 months, and stayed at a moderate. Dh decided he enjoyed going to WDW more than he had thought he would so suggested buying into DVC. We have gone about 5 times since then and haven't always stayed in our DVC home resort of BWV. Since I get the AP now, I tend to make a short last minute trip if I get decent airfare. But, if you plan on going to WDW at least every other year, and tend to stay in the deluxe resorts..it might be a thought.