First, there is no liability insurance on the fifth wheel. Not sure what the Liability and Underinsured is that you quoted, since the liability portion is on your truck.
There should only be comp and collision.
If you are not a full timer, and someone gets injured at your campsight, or falls on your fifth wheel steps for example, your Homeowners insurance will cover that for the " liability" portion.
If the quote you are giving in for the Grand Design in your sig, it seems a little low, but not too much.
Make sure you have zero deductible glass, and that it will cover the full market value of your rig in case of fire or the worst case scenario, and your rig is totaled.
Also check to make sure your awning is covered under the policy. Usually, most policies include anything that is permanently attached to the rv.
If you are a weekender, I would guess about 1-3k contents coverage should be enough, and is normally automatic on an rv policy.
They should also give you " vacation " coverage, so if your fifth wheel ends up in yhe shop, they will pay for a hotel.
Liberty is pretty good about multi car/ homeowners policies, so that is most likely why your rate is so low.
We paid $87 for a year when we were weekenders, but we were also in Phoenix, which was considered a high crime/ theft area.
I would call your agent tomorrow and check on the coverages mentioned above.
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