There's a bug in the 22B. You buy the Engine stage 1 upgrade. You go back to buy stage 2 and it tells you that you need Stage 1 even though you have it. When you go the Base Engine or go back to buy Stage 2 and you don't have funds for it then Stage 1 disappears. It's done it twice on me so I lost 4500 twice.
I have all upgrades except Engine and all but Turbo Stage 2 up.