Hi! I got asked to go a cake demonstration for a kids event. Probably something simple (basic building/crumb coat, top coat, then some buttercream designs on top. 

How much should i charge for that? Probably less than one hour....

Will you be Reimburse for supplies?  How charitable do you want to be?  Since it’s for kids I probably would ask just like $25-$30   You need to ask yourself if you can afford the time   Just random thoughts