Roger that basskat. I worked a summer in Memphis TN years ago doing concrete work on the Firestone Tire factory roof. I don't know how you guys do it dealing with the heat and humidity. I'll take snow and ice over those summers any day.
Re: Storing your boat outside come winter. I may be preaching to the choir here but make sure your to keep your cover cleared of snow and ice. I didn't check my cover a few winters back and wound up with a block of ice in my boat about 1 x 4 x 6 foot. What a treat that was thawing/chipping that out without a heated garage. Hint, Pull your drain plug too. I didn't = DOH! I only have one boat now so the boat stays in the garage all year when I'm not using it.
So, your thinking of making your shooting/casting room a permanent fixture then? You would have to heat it 24/7 unless you wanted to tote your liquid supplies too and from the house each time you wanted to shoot. Humidity could be an issue for your hooks so maybe a dehumidifier would be in order too? Yes, I have been mulling over doing the same thing with my garage in case you couldn't tell. LOL