Another thing I think is noteworthy is I am not sure about all insurance companies, but mine (American Family) will not cover you in the event of your deck crashing. If someone is injured, then it will pay up to your liability amount, however, if the deck breaks due to overload or poor construction, you are pretty much SOL.
I personally built my 8x10 spa deck out of 2x10 pressure treated, and brought a header under the entire structure just to be safe.
Jr.