After your initial deposit is received, you send them how ever much you want, whenever you want. I do it every trip. As soon as we return home from WDW, we call the next day and book for the next year. Then every week, or month, whatever i feel like, i just send them a check, or fax them my CC info. Then when its time to go, its paid for. I figure out the total amount due and just divide by 12 months, so i know what i need to send them every month to be paid off before we leave. Sometimes i send more, sometimes less. I have this trip paid for except for the annual passes we are buying and i am only $100 off from that and we leave in about 2 weeks, so all is going according to plan. I also set aside an envelope in my house and vow to put $60 week into it, so in a year, we will have about $3000 to bring with us. Last year we only spent $1500, so when we returned home, we already had the money for the airfare for this year and then some!Paying it off thru the year is the only way to go in my opinion.