20$ is a lot for BBQ. I can feed 10 people with that. I also have a financial advantage coming out of college a couple years ago.
With that being said this is my favorite recipe for big groups for cheap. Add frito corn chips and cheese and I promise it will be amazing. I crock pot mine for 10 hours.
Taylor-WSM 18.5 with Wifi Stoker, Kamado Smoker BBQ, and lots of charcoal. 180 club-Chicken