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Obviously the majority of sales are betwen $6k and $8k but a succesful dealer has product that moves at the top and bottom ends as well. There are plenty of spas sold at successful dealers between $4k and $6k and from $8k to $9k and even $10k, and I don't mean 10% on each end. Ask dealers of some of the big guys like Marquis, Sundance and Hot Spring if their high end spas (Epic, Optima and Grandee) are mostly filling floor space or if they sell well and you'll find that they are each one of their top sellers (in quantity, not just $$) yet they are $9k+ spas. Each of those sell quite a few also between $4k and $6k (like Capri and Jettsetter). Their strength is their ability to sell through from top to bottom.
As far as the $10K plus spas... I am certain they do sell fine in "some" markets... thus my recs for a solid $6-$8K mfg option. That's all