Echoing a sibling comment, lots of landlords require it now, and the basic packages that insurers offer you as a bundle with auto or other forms of insurance are pretty decent, depending on state.
Typically seems like $100-200 per year for coverage that would handle the loss of most of one's possessions, provided you don't get screwed by "well, you don't have the receipt" or "we only cover water ingress, not floods or leaks".
What do you consider useful? While I do not know how easy it is to make a claim, but my policy is a bit over $100 annual and covers some $20-30k loss. Which feels more than sufficient.
Hopefully, I never have to use it, and it is just a tax I pay.
I'm talking about people buying houses near a river that floods regularly and not purchasing flood insurance. Someone else brought up renter's insurance in response to my comment about flood insurance. Renter's insurance is cheap, btw. I have something like $300k coverage for less than $10/month bundled with my car insurance.
Probably a lot? I've moved around a bunch over the past 20 years, so have had several landlords. I think all of them for the past decade have required proof of insurance when signing the lease. I don't think anyone I rented from required it before 2018ish
