The average day spa visit costs $100 to $300. The average Costco spa and self-care haul that creates a comparable experience at home costs a fraction of that — and creates an experience available every evening rather than as an occasional treat. Costco has quietly assembled one of the most commercially compelling at-home wellness and self-care product ecosystems available in American retail — from the SaluSpa inflatable hot tub with built-in Wi-Fi that brings the luxury hot t