LOL. Which is why I came up with the "easy to do" Spaghetti Idea.
Other options right now are:
BBQ - $15 per person
Mexican/Taco Bar - $800 last time we did it but might be closer to $900 now. Mexican restaurant near us provides the food.
????
But when you start thinking about the logistics of spaghetti & all that's involved - if you're the one doing the purchasing, prepping, cooking, & transporting - it's really not easy at all.
Most of the time, around here, BBQ is going to come out as your least expensive option - but a catered BBQ meal here is pulled pork, BBQ sauces, buns, baked beans, & slaw.
This past summer for our son's 16th birthday pool party, I had a taco bar catered by Salsarita's. An employee, dressed in a nice catering outfit, brought all the food, warming trays, & serving utensils to the clubhouse, set everything up for me, & then left. It was easy-peasy for me! The only other food things we brought were the drinks, some fruit, & the birthday cake. I absolutely loved it & told DH that, from now on, ALL our birthday parties are going to be catered.
I think a Taco Bar could be really fun & festive! However, it's probably not going to be your cheapest option.
I'd also price sandwich trays.
If you like the pasta idea, I'm sure there are also some local Italian restaurants that will cater pans of baked ziti, salad, & rolls. Catered pasta might end up being more inexpensive than a catered taco bar too.