Repairs - pumps wear out, heaters stop heating, and other mechanical problems inevitably come up. Read and understand the manufacturer's warranty before you buy, looking for key points like coverage of parts, labor and other materials. Also, look for hidden fees and other costs you may incur if, for example, a repair technician has to travel from out of town to get to your location or if the local supplier does not keep a specific part in stock. Some warranties on portable home spas even specify that certain types of warranty repairs must be done at the spa factory, requiring you to pay for shipping to and from the factory.
After shopping at your local spa dealer you might be discouraged with how high the prices are. Even the discount factory warehouse chains sometimes seem to lure you in with a low price in a newspaper ad, then try and talk you out of buying the advertised one and spending instead on a top of the line hot tub. They will use arguments like, "this discount tub is a closeout and the technology has come a long way since this has been manufactured". Or come up with things like "the insulation in this other tub is much more efficient", "the motor is more powerful", or have some other reason to steer you toward a more expensive tub. Some of the things salespeople are saying might be absolutely true, but they are trying to play on your fears and emotions to get you to spend more than you might have initially budgeted.