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That is a deal, just the material will be way over $450.00 GFI panel $250, Cabel 6 wire $25.00 @ yard and breaker between $30 to $60 plus labor aprox 2 hours plus service call... I would say you got a deal...
I just had mine done for 485.00 but I bought the box from the hot tub dealer for 100.00.in California, I paid 1,100.00 to have it done, 220 volt, here in NC it was a lot less.my tub can't come soon enough!!!!