When we bought our first trailer seven years ago, we got a quote on a "premium" EW. We then put that amount in a MoneyMarketAccount at an on-line bank.
We have paid for replacement of a couple of failed items (microwave, etc) out of the account, but now have a sizable amount of money available if we should have a major failure
Consider it "self insurance" and better than paying somebody else during the times when nothing fails.
One consideration is that being retired I do most repairs, including major work like replacing the thrust bearing in a landing gear leg, myself.