Is there state tax on all real estate rentals in fl?--regardless of duration?

A rental is income. Income needs to be reported.

Are you asking whether you should be charged sales tax when you pay your rent? If that's the question, according to:

FL Dept Rev - Florida Sales and Use Tax

Businesses involves in "Rentals, leases, or licenses to use real property (for example, commercial office space, mini-warehouses, or short-term living accommodations)" must collect sales taxes. I don't know how they define "short term."

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