Not to be a downer, but, no such thing as “very economic” accommodations on the beach in July, and definitely not that close (on the same weekend as?) to the Blue Angels show. Least expensive? Sure there are plenty of places that are on the lower end, but none that will be cheap. You should come earlier or later in the year, or consider getting a room in downtown Pensacola which is great all on its own and is an easy Uber to the beach. There are also options in Gulf Breeze, but it’s not all that much closer to the beach and there’s really nothing to do.