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That buying guide is for hot tubs in general. Not caldera Spas. That's the biggest point you are missing
If you want value and not roto-molded, then Nordic and Viking are good options. Maybe the South Seas brand from Artesian.
so it seems preposterous when an expectation of double that for dealer costs on a similar tub (not necessarily more than twice as good)
Value priced is $4k -$7k in my opinion excluding roto-molded spas.
I am going to be the ass here...