The Keys you could spend for ever. Amazing place
I can't remember were we stayed but (Down town Miami) went walking around looking at shops at about 4:30 ish on day of arrival. Folks were very friendly and almost seemed more surprised to see us their. All non American locals. Anyway eventually one shop owner insisted it wasn't safe and should immediately go back to our hotel. That was when we realised we had half a neighbourhood following us waiting to see us get rolled

Very scary.
But even funnier was the other group who got on the Mono rail. They had a message come over the speakers to lock the doors and only open then at the next station were the Police were waiting and escorted them back to the hotel. Apparently it was so unsafe, the Mono rail ran drive less after dark

Needless to say we got a bit of fright as a group..
I found the most fun i had was to sit and just watch the people go by..Everything else was second to the people and characters
Upstairs Burger King at Keywest is the best location
It is on my bucket list to sail/cruise that part of the US..