When the rules specify a certain minimum of Core units, is that the actual number of units or unit types?

Likewise with the Elite units, is that a maximum of actual units or types of units?

I'm not quite sure I've ever gotten that...

Actually, for Core it's total number and for elite it's a maximum for each type.

So if you have a core requirement of 4 and an elite max of 2 you need to have four total core units and can have 0, 1 or 2 of each type of elite unit.