If I want to strip my car to the metal..... what do you recommend?

That's unfortunate for me, its as big as I felt I could fit in my garage.

"a 6hp 30gallon air compresser max 150psi"

You can blast with that. It's not ideal, but that's about the size of the first one I used. Had to wait for it to catch up pretty often, to the point it was a bit annoying, but it's big enough that you can make it work.