If you are patient you can get a good rate at least 7 days before your trip begins. That is when the last minute rental rates are released. I never book my car until the week we leave and have not paid more that $90 for a weekly mid size rental for the past 3 trips I have taken to WDW. Also I would sign up for
Alamo free Insiders program. They offer their Insider member high coupons than what is offered to general public.