Are you asking how much sauce you need per cook?
When I make sauce I usually make a big batch & put it in a large ketchup bottle. Use what I need & refrigerate the rest. It lasts for months in the fridge.
As I was about to toss out the ketchup bottles, I had the same idea! I'm preparing a socially distant BBQ lunch for three friends and this will give everyone their own bottle of sauce. Now, how to get the thick sauce into the bottles...