For Walt Disney World vacations all you have to do to reserve your room is put down $200! Then you have up until 45 days before you leave to pay off the rest of your balance.
You don't have to make payments each month either. You can pay it off however you choose. Let's say you have some extra money one month and would like to put it towards your trip, all you have to do is let me know and I can apply it!
Once the $200 deposit is down you can start making dining reservations and any other reservations that you would like.