I never used too because most of the time they were starting asap anyways. Than I had a few spaces open up a few months down the road and I wanted to make sure that they were committed to it so I started charging a holding fee/deposit and I increased my notice of withdrawal. The one week payment is used as a non-refundable holding fee and once they start care, it then turns into a one week payment that is used towards their last month's fee. I also charge 2 weeks in advance, so their first payment is for 3 weeks. It can be a lot of money for some all at once and I do think it has turned some away but I'd rather do it this way than risk getting screwed over.