You are not likely to be able to just walk around marinas and look at boats. First, you'll need an appointment through the listing broker to even get on the boat. Second, just about every marina I know down here is gated and you can't get in without an owner having approved your arrival through the office.
My suggestion to you (this is what I did) is to do your shopping on line at YachtWorld.com and pick out some potential candidates that are located in Florida, and then hook up with a broker who can arrange for you to see one or two each day, depending on where they located. I flew into Orlando, rented a car and headed over to merritt Island where I looked at a 53MY, from there, I had a 58TC lined up to see in Stuart. Then I headed on down to Pompano Beach, Fort Lauderdale, and Miami where I looked at several 53MYs and 58YF and finally drove on down to the keys where I found saw a 58MY. Then, flew home out of Miami. Ed and I did this over a several day span, but for a trip like this to be effective, you have line up the apointments in advance, NOT when you get to Florida.
We did a similar tour when we flew into Tampa, surveyed a YF in Clearwater (which we rejected), drove on down to somewhere south of Fort Myers and looked at a 53MY, then went on over to Miami and looked at a 58YF and then I found my "Sanctuary" in Miami and bought her almost on the spot! All of this worked like it did only because I had all of the appointments lined up before I even bought a plane ticket.
You don't need to deal with a bunch of listing brokers. Call anyone and have that broker set everything up for you. Although the broker that will then be working for you won't necessarily be at all of the showings, that broker will have arranged with the listing broker to get you on the boat.
P.S. The boat in the title picture appears to be a late model (curved PH windshield) 53 MY, extended deck - did the 53ED lack the walk around decks like the 58MY does? It is not a 58, 61 or 63 - there are not enough windows down the side for that. Those boats all had a second set of windows all the way aft.