-Build behind tech (normal cost).
-Call-in on the screen with extra cost to call them (battlegropus 20% extra cost and +CP)

example 1:
I want to get a 200MP inf unit, and I do it through tech, which is a normal cost.
it would be 200MP and 0CP
example2:
I want rush and I use via battlegroup (it's the same unit as example 1), but with a 20% extra cost and +1CP
it would be 250MP and +1CP
example3:
I want rush and I use via battlegroup, I want a tiger (600MP 150FU 20pop), but with a 20% extra cost and +3CP
would be 720MP 180 and 23CP
you do not take the numbers are indicative, take the idea.
It can also be a 30% tiger would be 750MP 188FU and 23CP
That is, I have those two options with each unit call-in
With the idea of having 2 callin options Coh3 we follow the trail of coh1 and coh2.