In short, most hot tub deliveries are made using a special wheeled cart, with the hot tub standing on its side. This means that you'll need to measure clearance from side-to-side in all areas of the pathway, as well as overhead clearance. You'll also need to avoid sharp turns, stairs, and obstructions in the pathway.
If your measurements don't allow for conventional delivery methods, a crane can often be used. While this may sound expensive, most crane installations won't cost more than a few hundred dollars and can be arranged by the dealer. However, keep in mind that dealers generally only cover the costs of a standard, typical delivery. If a crane is required, you'll most likely have the pay the expense.