If you hold a space for 5 months at 200 a month you have to consider the following. The client has now paid you 1000.00. If you terminate this child in the first 30 days (maybe behavior, maybe just a bad match. ) is the client going to feel owed something? Is that frustration worth turning people away for 5 months? And on those 5 months what is your potential income from that spot?

If the are filling a space that month then I wouldn't take a fee until 3 months prior. It's too soon. Anything could change.

Don't commit yourself too far ahead.