Why not replace the small fans with
solar powered vents. A simple solution that lots of people use. Whatever the cost, it'll be cheaper than installing an AC system or burning down your boat.
So long as the dock has a breaker (which you say it does), running an extension cord to the boat to use a power tool is fine. An inline GFI would be nice, since you are working around
water. But never leave the cord plugged in unless you are there supervising it.
I removed the AC system from my C&C25. Then I secured a
plug in a safe,
weather shielded location in the
cockpit. When I occasionally needed AC, like to run a
battery charger or drill, I would use an extension cord to connect to shore. But both ends were secure, not just laying about. And I was there supervising. If I had to go, unlplugged at the post.
And finally, if you are just running some power tools...you might consider
battery operated, rechargeable power tools. Are you talking about just a drill? And if you have 12volts aboard, why not use a small
inverter for the little bit of AC you sometimes need.
I totally agree with you...AC is NOT needed on a small sailboat. I enjoyed removing all the AC
wiring and accessories from my boat. You can replace your battery
charger with a small
solar panel.
Best of luck, and please let us know what happens.