I don't know about foster, but for straight adoption, the worker came to our house 5 times and spent 1.5 to 2 hours talking with us about ourselves, our family, our kids, childrearing etc. We had a great caseworker and it was all rather pleasant. We'd started with another agency and their caseworker just raced through everything. I really wondered how she could do everything so fast. That agency didn't work out for us.