[NYGUY]

Originally Posted by Bosoxfan

Florida law allows up to %20 of people to be under 55.

Originally Posted by Bosoxfan

Home / Resources / 55+ Housing / Requirements
Requirements
Federal Register 24 CFR Part 100; section 760.24-760.37 (4a), Florida Statutes

For a community to be considered "housing for older persons" as a 55+ community, the housing must be intended and operated for occupancy by persons 55 years of age or older and meet the following requirements:

At least 80% of the occupied units are occupied by at least one person 55 years of age or older.
The facility or community publishes and adheres to policies and procedures that demonstrate its intent to in fact be a provider of housing for older persons.
The facility or community complies with rules established by the U.S. Department of Housing and Urban Development (HUD) for verification of occupancy.

I think similar Federal Law controls in this case and I doubt you can pick out any age below 65 to satisfy yourself as the OP suggested. I am going to guess that 19 is part of the law.