As an insurance claims person, I will throw in my $.02 worth and make a few general observations.
1- Homeowners coverage will generally cover tractors "used on premise exclusively to service the residence premises." Therefore, if you are off premise, or hiring out commercially, you likely won't be covered.
2- Assuming the above, the tractor should be covered similarly to the rest of your personal property, i.e. if you have all-risk, the tractor will be all-risk too. This also should apply to replacement cost. My company paid a claim where an insured's worn out 10 year old zero turn mower burned up. We laid out about $9,000 to replace it with a new model of similar type and quality. I have since wondered what the heck we would do if someone had a Ford 8-N or something like that. Would we buy them a brand new NH utility tractor?- I have no idea.....
3- I can't see how rolling the tractor into a tree is covered and rolling it on the ground not. Most contracts define "collision" as "collision of the covered vehicle with another vehicle or object, or its overturn"
4- The statement about hauling your tractor is correct. If the tractor falls off the trailer and causes an accident, the liability portion of the tow vehicle's policy will cover that, but you will need coverage on the tractor itself for the the damage incurred to the tractor from falling off the trailer.
5- Many homeowner's policies will automatically provide a nominal amount of coverage($500-1000) for utility trailers. Some auto policies may also provide a similar coverage. You should check your existing policies to see. If not, you may also want to consider buying physical damage coverage for your trailer. Remember you will have liability coverage under the vehicle towing it.
6- "mysterious disappearence" is a very unlikely issue for a tractor. You will more likely see it with a quantity of items, livestock for example, where you know that on a particular date you had 60 head in a pasture and 2 months later, you counted and found you only had 50 and there are no dead carcasses in the pasture. In other words, you can't state a certain time period and the is likely no evidence that someone came in to steal them. Another example may be someone who realizes that their ring is missing, but they don't recall specifically if they were wearing it, or had left it laying someplace, etc., but it is now missing.
DISCLAIMER- These are general issues, and your policy may be different, it is very important to read YOUR policy and ask any questions of the agent or local claims rep if you don't understand something or need a clarification.
