I can't coment on the brand itself or price but...
The illuminated ozone icon indicates that there is an ozone system connected to the tub. There are 2 types of ozone systems: UV (uses a UV light bulb) and CD: uses a spark plub type doo hickey. The ozone unit if UV may need a new bulb. CD units also don't last forever. Ask was this a factory installed unit? Did they ever replace the bulbs?
as far as checking out the tub, some of the things I'd look at are:
Open up the equipment bay and look for moisture and inspect the unions and plumbing. Look for signs of leaks rodents, decaying joints and hoses. Since this was an inside tub, the equipment are should be **** and span.
Make sure all the jets are working. Work all the jets and diverters. Run the pumps at all speeds. lsten for nosiey pumps, excessive vibration, strange sounds, etc.
Take a good look at any pillows. These might be in need of repair.
Look for blemishes in the shell and repairs to any cracks.
Take a good look at the exterior cabinet, the cover, lifter and steps.
Inpsect the filters. It maybe a good idea to figure in purchasing new filters.
I'd also take a look at how to get in and out of the house.
Don't forget to ask about the electrical box (who will do the disconect?) Are the box, breakers and wire whip included?
Ask about supplies and other freebies they might have laying around. (vacs, chems, test kits, manuals) etc.
Can they give yo uany history on the tub? When it was bought, how much paid, any repair work, why are the selling....
Are they going to let you wet test?
Good luck!