A good cost is more about what you think those items are worth. I can tell you the cost of overhead HAS to play a part in the cost of the spa. If you live in NYC or Buffalo I would imagine there would be maybe a $1500.00 difference in pricing. Its not that your getting shafted if your in NYC, but if you want that dealer to stay in business to help you for the 15 years you own that spa, they better beable to afford the rent! Figure out what your comfortable spending and go with it. See if they have a floor model or instock model they might be willing to discount.
I wouldnt hold the Limelight in the same standard as the Vanguard, to me (and this is only my opinion I have VERY limited access to those spas since they have came out and they have changed alot since I did have access to them) is they are Watkins line trying to be more similar to brands like Master Spa and Dynasty. Im sure they are ok, but if you like the Hotsprings because its reputation, I am just saying Limelight might not deserve the same reputation Hot Springs has (again thats my uneducated opinion).
I dislike the Ace System because you will still spend money on chemicals and no way the 1000.00 or whatever they will charge for this system will ever be paid for. Also keeping in mind it wont last forever, I believe it has a 1 year warranty but you may want to ask the question.