Nick,
I moved my boat from Chicago to Punta Gorda, Florida last May. Many of the folks that have already replied gave me a lot of solid advice. Here is what I have learned so far. First my boat is a 376 with a 5' draft. I come and go out of the Ponce inlet. I have not touched the bottom yet in any conditions. I did bump a little when I left the Charlotte Boat Yard last May but since then I have not. I know I will run a ground sooner or later but I have been luck so far. Staying on the depth thing I put my boat in Fisherman's Village Marina for about 5 months. Nice people, pretty nice place, but many times I was setting on the bottom so if you go there make sure your in a slip as far out as possible. Like you I had hear many things about getting the bottom ready. Here is what I did.
1. Sanded down to glass, filled any small blister and anything else.
2. 6 coats of WM 2000 barrier coat. The box said only 5 but I had some left over so 6.
3. I used Red and Blue WM ablative paint. Two coats of red and 3 coats of Blue. My plan was three coats but the paint went further than I thought so ended up with 5,
4. New Zinc. This has been the big problem for my boat the zinc goes very fast. More on that later.
5. Prop and shaft. I was so confused on what to do I waited until the boat was delivered. The guys in Charlotte Harbor Boat Yard helped me decide. I put several coats of a red metal primer then a hard paint they gave me for both shaft and prop. Basically you cannot stop the growth there just slow it down.
So how has my bottom done. First you need a diver this can be monthly, 6 weeks, 8 weeks it seems to depend on your prep and in my case the zinc. The diver I use charges around 65$ per visit. Sometimes less some times more depending on what her finds. He brings the zinc with him. My bottom is doing great the diver says he mostly finds slim and very little "hard growth". Basically he tells me he would not dive on my boat more than 8 week intervals except for the zinc. The zinc is going very fast I would say while in Fisherman's village I had to change the zinc monthly. Based on what I have learned there are several reasons. First high water in the marina this summer ups the zinc usage. Other boat in the harbor also help eat the zinc depending on how they are wired, and my boat seems to like zinc more that others. This is because my zinc mitigator (small thing in my wiring compartment that helps me fight other boats stray current) was dead. So I had to replace it. I also must have something not grounded right (I am still working on this one). If your like me my zinc in Lake Michigan was maybe 2 years old I never thought about it. The good new is since we purchased the home and the boat is on my own dock the zinc is lasting longer. Last dive was a 7 weeks gap again the bottom was great, light growth on prop and shaft, and 50% zinc gone. This is a big improvement but I still need to find the issue. A short term solution is two zinc;s.
A/C is important as you know but what I learned is the water down here gets very warm also. When that happens your A/C runs 24/7 just to try and cool things down. You may have two systems so that will help. The 376 is just on the edge of needing two system. In Lake Michigan the water was always cool so my A/C did great. Down here it ran and ran and ran. So know where your condensation is going. Many boats from the midwest just dump the condensation into the bilge. So here is the story. My condensation goes into the bilge and when it gets high enough the bilge pump dumps it out. The issue is that leaves moisture in the bilge and in the boat. The bigger issues is your depending on the bilge pump to work or your will fill you boat with fresh water condensation. This happened to me. The A/C in the summer will put out 1 gallon of fresh condensation water an hour (24 gallons a day). If your bilge pump fails the A/C keeps putting out the water. My bilge pump failed because the wire connect was done for the Midwest. After a couple of months here the connects just rusted and the pump stopped. The water made it to the top of the bilge before I found the problem. Close call. I was not around my boat everyday so that also caused the problem. Just check some of your critical connection and use something better than electrician tap to protect these connections.
I also will cover my boat this summer to help keep the direct sun off the boat. Shading the boat really helps keep the A/C also.
I fresh water wash down my boat once a week of so and have applied protection stuff on my dodger plastic once every 3 months. Having hatch covers etc also helps. For me the boat is much cleaner down here than in Chicago. I think the big city put out a lot of dirt so I find cleaning the boat is much easier. Ground tackle. Listen to the group I got lots of advice. At first I was thinking about all chain for two anchors. A lot of cost and very heavy. Around here all chain seems to be over kill since you don't (I am told) really put out that much scope because of water depth. I guess if your going places outside this area you may need more.
Top of the mast has been an issue here. I had never gone up my mast in the 7 years I owned the boat. But here I have had to go up 4 times now because the birds of pray like the new stick as a fishing platform. They do not like all the wind instrument stuff so they take it off. I replace the vang on my wind instrument the bird broke it off. I am now replacing the visual vang because the birds decided they did not like that either. I wish they had made these decision all at once but two different birds I guess. They also make a real mess on the boat. When they are on your mast they go to the bath room all over the boat. 61 foot fall of pup big splash you get the idea. The good news is once your mast is not new anymore they seem to have moved on. Just part of the welcome to Punta Gorda thing.
Dehumidifier has made all the difference. I first believed my A/C would clear the humidity out of the boat. But that just did not work. The small replacement dehumidifiers just did nothing. So I took advice and purchased a small dehumidifier from Home Depot. I put it on the boat to cycle every 4 hours for 4 hours. I set it up to drain into the sink so I did not need to pump anything over board. Man what a difference. When I go sailing I just put it into a secure place in the head shower area and off I go. When I am back at the dock I put it on the counter top with hose to the sink and turn it on. I would get one that has all the auto shut off stuff. This has been a big learning.
I could go on but will not. This is a great place having the choose to sail the bay or go out into the gulf is great, The folks down here will really help you out. Several checked on my boat while it was in the marina just because I was worried about her which was fantastic. If anything I have suggested is off base they will correct it. I am not an expert.
By the way there are several sailing group, The Mariners, The Seafarers ............ They all cruise and do all kinda of stuff. Being to busy down here is a really possibility you have to pace yourself.
you lots of good canals and lots of boats with 5' plus here in PG.