Be sure your contractor knows about wiring HotSpring Portable Spas - they come with a sub panel which contains two GFI breakers. He will need to run a 50 amp (four wire) service to the sub panel, and then he will have to run six wires from the sub panel to the spa: two #10 wires, three #12 wires, and a ground.
You can download a "pre delivery instruction" booklet from the HotSpring.com website, under "For Owners" tab near the top right. That should give him the info he needs.
And yes, I'm at least over halfway serious - but I don't know if we could pull this off. Yes, I AM in California, and yes, our daughter really did relocate to Florida, yes, I would love a road trip, but yes, the factory would require that I handle warranty work (or have it done by a local repair person).