Using State Farm and insured as a truck on a commercial policy even though it is a camper. Seemed easier at the time to show them a picture which is all it took to get them to underwrite the policy. Worked with a local agent which I think helps a lot when compared to explaining over the phone to an agent.
It has been a few years since I was in the US, but Pierre at Sathers helped us when many others said no. He is still listed as current staff on their website but I've no idea if he is still able to help.
Depends on how old your truck is. If it's over 25 years old and can be considered "Antique" or "Classic" then you don't have to deal with the big insurance carriers like I did. If it's under 25, or 20 years even, you're probably going to have to insure it as a commercial vehicle.
I went through a lot of trouble with State Farm, they classify Unimogs as a "Military Armored Vehicle" regardless of which version you have. They wanted to charge me $265 a month and classify it as a commercial vehicle and would not insure it and only give me liability coverage. This was after I told them it was a pickup truck and all the comments given to me by the guys over at steelsoliders forum. Seems as though State Farm has a template for this class of vehicle and their adjustor actually want to get my local agent in trouble for trying to cover it. I've been a customer with State Farm for years and this made me second guess them for all my needs.
A colleague of mine who works on Indian Head motorbikes told me to go to Hagerty. Sure enough they actually had Unimog in their vehicle list, they are based out of MI, I got 100/300/100 coverage and coverage for the purchase price of my truck, and while it's not my daily driver, I can still drive it to work a few times a month and I'm paying $191 annually for my 1965 Unimog 404S. Check out Hagerty (hagerty dot com) before you go anywhere else IMHO. I only had to send them a picture of my truck and I had my insurance card and was covered with in 24 hours of signing up.
I only recently found out that they have actual locations here in Louisiana I can go to if needed. (just not in my town)
I've had USAA for 39 yrs but they wouldn't cover mine because it is an RV/camper/motorhome, so they suggested I call Progressive which has an "arrangement" with USAA for RVs. $350/yr or 6 mos, I can't remember which, for 500k liability, no collision.
I just bought a 2003 U500 camper, since I have been with stat farm for years, I called my local agent for arrangement, they discussed it whole afternoon and replied me next morning,
50/100/50K, $500deductible, property damage value $50k only!!!! $89/month! I am thinking switch to progressive asap. people say progressive system has unmog camper listed in.