Seems odd that it wouldnt include delivery. Would make me worried about the dealer your working with. I would call other Caldera dealers in other cities around you and see what prices you are quoted. ask about included delivery and who to call in case of an issue with the spa. Hint: I should be them and not some customer service number, at least that is my opinion.
Have you wet tested? I highly recommend wet testing several brands before buying. I just purchased our first spa and initially I was drawn to Caldera because of the "salt water" system. Unfortunately thats mostly a lot of marketing. Its not like a salt water pool. its more of a salt cleaning system and the salt converts to chlorine. When we wet tested we were really turned off by the strong chlorine smell of the Caldera. I would suggest checking out Maquis, Bullfrog, Coast, Artesian. Definately stay away from any big box store brand at Costco or Home Depot. Theres is a lot of disdain around here for Master Spa. I dont have any experience with them but I would be concerned about buying from an online salesman and having to deal with some 800 number when you have a problem. But maybe some of their dealers are a little more local and hands on.
Personally we went with Coast. I really liked the powerful motors they use and the warranty is 5 years on parts and labor. Also I found a really good dealer that I felt comfortable working with. I had to drive 150 miles to Portland Or to find the spa we wanted but that saved us $$5000 over the price i was quoted from the dealer here in the Seattle area. Definitely take your time and dont rush into this. Consider it like buying your first car. Heck they are priced that way!
Good Luck. DM if you have questions.