DVC isn't a savings account where you can deposit cash and have it available for your trip. I'm guessing perhaps you are asking due to favorable exchange rates? If so, I know there are a number of on-line financial institutions that could set-up a money market account in your name. That's something to consider as it will have a fairly decent interest rate attached. Just be careful not to get locked into anything that will keep the money tied-up during your trip dates!
DVC does not have an accounts receivable system for cash reservations.
They have to be paid at check-in. They do take a credit card # as a guarantee, if you cancel less than 5 days before, they charge 1 night.