There are certain design and build considerations needed to build an inground spa in cold weather climates. Nothing insurmountable however. Custom in ground spas can start at $35k and go up from there depending on features. The economy of scales really has no effect because every aspect of a large pool has to be done on a small spa, just on a slightly smaller scale. Attached is another option of sinking a fiberglass shell into a design. This gives you the hydrotherapy benefits of a portable spa, while maintaining an outstanding aesthetic appeal!
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