I have had this conversation with many Florida investors. First of all, expect a massive discount, wood is not only much cheaper to build but is also much more difficult to maintain against termites etc, especially Formosan. A huge discount should be considered normal, and when you sell, your going to have to pass that discount on to the next guy. They just are not worth what CBS construction prices command.
As a cash flow rental though, it could be, just know what you are getting into. Get a lot of information on you termite history and report, get an inspection that has an inspector really familair with termites.
As for insurance, insurance is getting more crazy in Florida in general, a policy that costs several thousand dollars is pretty normal. Citizens is state run insurance which is like a last resort, I've never heard of Citizens denying a policy as long as you meet the criteria, so that's comforting in a way.
Hope that helps, know that all wood structures sell at a substantial discount, and really consider the termites. The good news though, if it was built in the 30's, who knows, maybe you have some great wood! Certain native woods in florida are actually pretty decent at resisting termites. Let us know how it goes, good luck!