Surely this has to be a red flag?

Just proceed with caution and be objective. 36% seems like a red flag (salesman trying to sell you an inferior product - too good to be true).

In looking at the allegations I'd say the primary red flag is the use of the word "guaranteed" when discussing returns.

My main concerns about Florida include: Chinese Drywall (very toxic; found in older homes); HOA Restrictions; Lots of people/crowds; sinkholes (properties sinking into the ground); Red tide (dead fish found on beaches due to algae bloom); Homeowners Insurance costs (w/older roofs); Mold; Hurricanes/Flooding , New construction (not always built to quality)... these are the most common issues found in the Florida market.What zip codes would you recommend for a single family investment property under 300k to mitigate these concerns? 

A few brokers in my office have tried but the red tape and time intensity has either killed the deal (seller got fed up after 90 days of escrow) or the property did not qualify. 

Quote from @Dav Pohote: Quote from @Alex Hunt: Commercial loans are much more lenient than conventional and a lot less red tape. 

Alternatively, you COULD also refinance and use the equity to purchase something with more cashflow which would allow the deal to 'pencil' without leaving you in the red every month/year. 

I'm actually in town until Thursday.At the very least, attend the Red Stick REIA meetup tomorrow night and see if you can find someone there with some experience who would be willing to help.

So things that are a red flag for me may be fine for someone who's more aggressive.

The lender will qualify you (there's a rather 'red flags list' that is used) - as well as have you sign all the occupancy declarations - that pertain to the financing prior to closing.