I just financed part of my DVC contract through my credit union using a signature loan. You could actually get the whole thing financed, they won't require a 10% down like DVC would, but I have to agree with everyone else about not doing this if you don't have the money to put down for a down payment. I look at it a little differently though, it's not about giving financial advice, it's about making sure you actually get to go to disney. If you can't afford to put forth a down payment, then it's likely you won't be able to afford to take a trip down to disney either. Purchasing into DVC is nothing more than getting a place to stay, you still need money if you want to do things. If you're stuck trying to make yet another payment on your DVC property, then chances are it's going to be hard to come up with the money for the actual trip.
When I made the decision to do this, I financed a portion and paid the 10% myself, even though I didn't have to, and, I made sure I'd have enough to go to Disney as well this summer, without putting myself in any financial hardship.