Modification Costs

First Plane
Your first plane will always be the I-16. You got to start with something... Right?

Second Plane
Your second plane could be... TBF C205 FR-1 It's likely TBF will be your second, unless you sequence-break to Vettore or Embargo and buy other planes.

Third Plane
Your third plane might be...TBF C205 FR-1 J7W or He162A-1

Forth Plane
Your fourth plane can end up as... TBF C205 FR-1 J7W or He162A-1

Fifth Plane
Your fifth plane is one of these...C205 FR-1 J7W or He162A-1

Sixth Plane
The last plane obtained is...C205 FR-1 J7W or He162A-1