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He plans to set it into the ground; we'll get any permits, but it is the maintenance issue I'm thinking about.
2) I would highly recommend you partially sink the spa rather than fully or at least consider it. There are two advantages to the partial method, a) if you leave about 12 to 18" exposed it makes it MUCH easier to enter/exit since the surface outside the spa will be about even with the spa seat you'll be entering at, b) it allows use of a cover lifter (depending on the model) which I think is a major addition.