I have all my stuff insured through State Farm. House, new island camp, motor vehicles, boat and snow machines, plus I carry an umbrella policy and term life insurance. Yeah my insurance company likes me, but then again carrying everything with one company does give you access to well in my case volume discounts.
Couple things to consider. Read your umbrella policy well, many of those require minimum levels of coverage for your first line of defense. Also in my case failure to cover insurable items can void the umbrella policy too. For example if I didn't have liability on my snow machine and got into an accident on one, my umbrella policy would not cover me.
Secondly, USAA was mentioned, even though I qualify as a vet, I looked into them and much of the insurance they sell is underwritten by others, so when it comes to claim time it's not USAA that is going to pay out, as they are just insurance brokers. A complication I didn't want to deal with.
I'm no insurance guru I'm sure there are some folks much more knowledgeable on this subject than I am. What I will say is that I've been with state farm now for 20+ years and the few times I've needed to use my insurance they have been great to work with. Whether or not they are the cheapest out there I can't comment on, but like anything sometimes you get what you pay for too.
**One disclaimer here, I'd need to check but State Farm may not underwrite my term life insurance, but in the grand scheme of things what do I care at that point, think I'll be dead

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