We just went through fostering classes. In our state, they do not cover daycare costs. They do give you a stipend for food and clothing, things like that. In our state, the minimum stipend is just over $600 per month. That's not near enough to cover daycare costs.
I was single for 6 years of doing foster care. My mom was my babysitter who also provided transport to visitations. I paid her so much out of the check each month for doing it. For the younger ones it is one of the best things because they quickly have stablity in their lives. They know exactly where they are going and they get a lot of one on one attention from her & my dad.