i dont think the bpv point can be change in sfc2, for what i have see the total for the ship cost is base on the weapon and power the ship have, you can change the bpv but the ship cost is calculate on the weapon and warp power, if you use shipedit take 2 ship like the f-ca and make a copy of the ship on the copy chnage the weapon and power make sure you give another name to compare so go in the game look for that ship and you will se how much it cost.