Yup, hang up what you can, I might figure out a shelf to stack the mowers, maybe even over the blower, make the table saw fit in to/under a front shelf as you would have to pull it out to use it anyway and like you said hang the trailer or back it in under the other shelf, could even nose the front of the tractor into a cubby under a shelf. I would put a workbench along the wall where you have the mowers so its where you enter the door instead of jambed at the end of the building in front of the boat. You didnt say how much land you have or zoning problems but I might be thinking of how else to store the boat. You already need casters,, I have made some simple covers, you could even use painted sheet metal and make up a cover for the boat,, or add a lean to. If zoning wont allow it there is nothing stopping from covering the boat. Even brackets and some really good tarp. I might go so far as to put the mowers and some of the summer tools on the boat under the cover for the winter. This is just me rambling but sometmes it pays to think out of the box a bit. This place looks wide enough but the shelves on the bench on the end takes up length, make the shelves in the front narrower. I bet you could get a car in there if you had to. Some overhead shelving on the walls may be useful, shelf where the saw is, tool box integrated under the bench.
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