i come from a family that chips in and helps, we generally don't cater the smaller simchas
so coming from that mentality -
cant u ask a friend or some bochrim, or someone that is good at making food and set up to do this for you for a specific price (price of supplies plus x amount) its not something fancy that u need a caterer for,
anyone can buy bagels, spreads, mezonos, juice, paper goods... and put it out
i have seen plenty brissim made by family and friends. much cheaper then $8-$15 a head