I'm sure there might be a thread out there about this too...sorry in advance. If you know if the link, please do share!
How many in-house cups should I plan for? Our sizes range from 8 oz, 10 oz, 12 oz, 16 oz, and 18 oz, depending on the drink.
First I don't and wouldn't have porcelain cups in 2oz increment sizes. Both from a so many beverage sizes "why" and from the good porcelain cups are expensive so the more sizes the more you gotta buy.
Second don't see anything listed for the core of espresso; demitasses for straight shots and macchiatos (we use 2oz for shots, 3oz for machs) and 5 to 6oz for capuccinos.
Regardless a number for any size porcelain will be based on how many you plan to serve in a "rush" versus how often you can be washing them. That can vary hugely by location. We have three locations, one using far more white porcelain cups (8,12,16oz) than blacks (2,3,6oz) while another about 50-50 and the third 2 to 3 times as many black cups.