I just got off the phone with my insurance broker. After about a year of back-and-forth (rural business people don't tend to hurry) it turns out that my Weekender is covered under my home-owner's policy. Now if I scuff the paint on someone's yot or accidentally run over a jet ski, I'm covered.
The actual coverage on the boat itself is minimal but that wasn't my worry.
That's pretty standard if under a certain value, but always good to check
I'm a surveyor for the largest yacht insurer in the country. One of the dirty little secrets they don't tell you about insurance, home owners or specialized boat policies is that almost all claims will be not their responsibility.
Lets say you boat sinks because a leaf fell into your boat and kept the bilge pump switch from operating (a fairly common issue). You'd think this might be an "act of God" being that you couldn't prevent the leaf from boarding your boat. It's not and you're liable for damages. Lets say the trusty engine you'd been using for a few years, still well below it's maximum hours before service, suddenly takes a dump. You're at full speed in the middle of a marina or mooring field, when the engine quits, with the resulting explosion (a little drama for color) also jams the rudder and you T bone a mega yacht, with your sprit, making a big hole. You're liable.
Darn near every event that can befall you, will be your liability, less of course an anvil falls from the sky and takes out your foredeck. It's usually a "catch phrase" under maintenance or operator responsibilities.
I discovered this when skippering a boat into a travel lift and the throttle stuck wide open. Before I could grab a switch or yank the "deadman" the mast had hit the cross bar on the back of the lift and the rig came crashing down onto the deck. The throttle stuck because a wedge shaped clamp, used in the linkage (since redesigned by the manufacture) fell out, preventing the return spring from having any leverage on the cable. Even though you'd have to have been a structural engineer, "back engineering" potential issues to find this problem before hand, it fell under the skipper's responsibility clause and the claim was denied.
In short, you have to pay a lot of money to get actual coverage for anything on a boat. Most times, you'll be covered for damage you do to someone else's boat, but damage to yours, generally is not their problem. All the contracts are aimed with this feature in mind. Unless you expect anvils dropping from the sky, you're pretty much out of luck.
Which is ok with me, I'm never worried about damage to my own boat, I built it, I can fix it, and with little boats like these, it isn't an issue with me. No motor to get stuck wide open either
 I'm only worried about liability and that I have.