Ditto to what everyone else has stated. It's your business therefore you make the rules but you also need to be the one who enforces them. Charge a late fee for late p/u...something that is a fair chunk so they won't want to pay it again and don't accept them back into care until it's paid. Get paid first, care after. Do you have a contract that outlines what is expected from parents and yourself? If you don't you best be getting yourself one. It makes life a lot easier and it helps weed out the less desirable families who think they're the boss and like to take advantage.