It is not about money, number of waves or related. It is about vital upgrade cards. Example : Integrated Astromech
Cost 0 upgrade quite critical to x wings. Something to fix it a little ok. You must buy T 70 blisters, Ok. It is a x wing fix in a x wing blister.
You open it and...ONE CARD. ONE. Perhaps you own many T 65, plus at least one T 70. Or more. And you buy a ship with ONE fix card. As I say very often, buy ships, not cards. But this is a little joke. Here your little fix. One per blister.
And the Tie / FO comes with TWO upgrade cards. Ohhhh man. Don't kid me.