I have a parent that has asked me to watch her niece for 4 days while her sister is in town. I haven't answered her yet but I'm not sure how much I should charge her sister. I care for 3 kids and that's my limit so this will make four, this will be out of my comfort zone. This parent usually picks up between 6 and 6:30 so I don't really want 2 kids here that late. I was thinking of telling her they have to be picked up by 5 for these four days and charging her sister a higher rate. I've seen some charge as much as $7/hour. My regular rate for her is $40 - I thought of charging her sister $50. Would appreciate any feedback on this.

Thanks