I think the usual deciding factor is place of residence, rather than delivery point, but there's lots of good information provided here based on actual experience. I believe that Casita
told me that I would not pay Texas tax, but would pay our GST, but since I didn't choose to buy their trailer I never saw how it would work out.
I know people in Ontario used the same phony Bill Of Sale value method as Gina described to commit tax fraud there, and apparently it worked. I suppose you pay your money (or don't pay your taxes) and take your chances. Not for me. I also would be cautious about dealing with any business which was willing to do this, since I would wonder what other laws they considered optional.