Again remember the weight of this hot tub. Make sure your decking can withstand this kind of heft. And how high off the ground is your deck? There has to be a way to get it up there. Consult the dealer to ascertain how the tub will be placed on the deck. There are cranes that can accomplish this easily, but not cheaply. It may cost $100/hour with about 3 hours of work. You wouldn't want this cost to be a surprise. You may even want to look into building a deck with the hot tub included. There are construction firms that will combine both. Just make sure you check their references before selecting a deck design firm to do the job for you.
Then look at the geographical location, and the distance from your home. If you have to cover too much real estate to get to your hot tub, there is a good chance you won't use it as often. Make its location convenient and pleasant. Keep in mind leering neighbors and your need for privacy and also just the aesthetics of your view. Much nicer to sit amidst the green of trees and bushes rather than next to a concrete barrier. And don't forget that the exterior of your spa needs to be waterproof. Pressure treated wood on the base of the spa is a necessity. There are a number of new options for this and any are good if they will keep the base moisture and decay proof.