I am a Realtor in Pinellas and Manatee county. I have helped clients buy homes or condos specifically for the use of Airbnb. I, also, have my own Airbnb. Unfortunately, there are no straight forward answers. It does take more work but it is definitely possible to find something.
Each municipality has it's own regulations. On top of this, each condo association or HOA also has it's own regulations. The condo/hoa will be enforced the hardest. There is a lot of user error from Realtors entering this information on the MLS. So, definitely double check with the association. I always recommend my clients double check with the city as well.
If your client is interested in this part of Florida let me know. I have some recommendations
Sierra Kluson
Kelller Williams Realty St Pete