My homeowner's policy is with State Farm. The basic coverage you get is very small. I added a rider policy that is very reasonably priced. They didn't ask for number or anything, just have proof of ownership if you have a claim.
I'm with State Farm and I'm about to sit down with them to arrange for a rider to go along with my homeowners on guns and some other items. I spoke with them a couple of months ago and they explained that a rider is better if you have to make a claim on it because it doesn't count against you homeowners. I may be wrong on that but it's what I took from the conversation. Once I get this done in the next couple of weeks I will report back with what hoops I had to jump through and what all was required. I was really leery about giving a list to the agent. I don't have a bunch by the standards that some here have but I've never let anyone know what all I do have.