I think she might be taking advantage of you so please be careful. I just opened my daycare so I don't have much experience but from what I have been told the nicest people who might consider you a friend are the ones who try to take advantage (in many cases not all!)

First, you need to decided if you want to do extended care. If you don't let them know this is something you cannot accommodate since you have a life of your own. Let them know moving forward if they are late it's a $1/min. I also do a 3 strikes and your out type of thing if families who are late. I understand that things sometimes happen but by the third time it turns into a habit and they are probably taking advantage.

The biggest advice I can give you that I have been told is to charge $1/min!!!! The only people who will have an issue with this are people who plan on being late. The idea of a high late fee is so that no one is late. $10 dollars an hour it nothing to people who make dinner dates or like suzie said above want to shower and get cleaned up before pick up. $30 for three hours is less then I think they would pay a teenager to come to their home to watch their kids for a few hours

If you wish to do extended care find a number that is worth your time. You are an experienced professional with years of experience and I am pretty sure they wouldn't except addition work hours for 10 bucks an hour. I personally would charge 20 dollars per hour per child. This is your time that is being taken away from other things like your children so YOU pick an hourly take that's good for you not them, if it doesn't work for then it's their responsibility to find alternative care not yours.

good luck