I went through this with my agent at State Farm. They've insured everything of mine since I was 16.
My homeowners only covered my tractor if it was sitting unused in my primary structure. If it was outside under a tree and the tree fell on it, it wouldn't be covered. If I had an insured accessory structure (shed) and the tractor was sitting unused in THAT structure, it would likewise be covered.
This came up when I started trailering the tractor places. I found out that my auto insurance did NOT extend to the trailer or contents on the trailer...only that if I damaged someone else's vehicle with the trailer, it would fix their damage.
I, therefore, took out a "personal effects" policy on the tractor. I figured the value of the most expensive possible configuration (tractor, FEL, BH, no MMM) and got a policy of that value. It is something like $120/yr.
My tractor is now covered no matter where I am, as long as I'm not making money on it. If I tear the MMM out of the bottom because I lost my brakes on a hill and hit a tree, I'm covered. If I pretzel my FEL because my throttle stuck and I hit something, I'm covered. The only thing that isn't covered is normal wear-and-tear...oil changes and the like. Even catastrophic failure (cracked tranny case) is covered as long as it isn't so old that it was EXPECTED to fail.
I'm not a fan of throwing money at insurance policies, but I can't afford to replace my tractor if something bad happens.
