At present, some performing arts organizations contract the whole performance. You should find such a company, first, to save yourself, and second, just negotiate the price with the agency.
I never thought about attending a wedding in the form of a band before. Doesn't seem to be very popular with the public. I don't think there are many wedding markets that need bands.
Our band used to shoot commercial performances, such as promotion scenes and discos. Never come to our wedding.