For a premium brand, middle of the road would probably be $9-$12k and high end $12k+. I consider the following to be premium brands: Arctic, Artesian, Bullfrog, Caldera, D1, Hot Spring, Jacuzzi, Marquis, and Sundance. Mid-tier brands probably won't be much less, maybe starting at $8k. The most well known brands I consider to be mid-tier would be :Master Spas, Maax, Vita, Dynasty.
I'm in the midwest, not NY, so I know your pricing is higher so I could be a bit low on my estimates.