We paid $370 a month for 3 half days a week (4 hrs/day) at a preschool associated with a church. We thought that was cheap though, my guess is the preschool was financially subsidized by the church, but I don't know. The teachers were seasoned and had been teaching for years at the same preschool (which follows a typical school calendar and is closed in the summers)
I have no experience with daycares, my impression is that it has higher staff turnover, maybe from teachers being burnt out and low wages, but I can't speak from experience.