In my screen, your photo is a bit small and fuzzy. The bike resembles the Schwinn Hollywood beach cruiser. Firestone sold Schwinn bikes under the Firestone name from around 1946 to the early 1950's or so. Serial numbers on your rear hub might give the "experts" on the Forums a clue as to how old the bike is.
The round seat stay curve and long section of straight tubing in front of the bottom bracket also scream Roadmaster. In NO WAY connected to the Wal Mart junkers. It was a different company altogether.
I am guessing early to mid sixties on the age. If I'm guessing right, it has a Bendix red band coaster brake?
Almost every SS bike used that hub during that time period, even Schwinn middleweights.,,,,BD
As far as value, around $125 max in excellent condition. It depends on the person buying it though.