Years ago we used to work for a 'home warranty company', it went something like this, a local Realtor would include a 1 or 2 year policy as a perk when working for first time home buyers, then if anything broke in the house the new homeowners would call the 800 number and they would send out the appropriate trade.
The insurance would pay us some flat minimum fee to show up, and we'd collect a $50 copay, then we'd have to get authorization to make further repairs.
I'd say 99% of the ones I went to were completely new and clueless homeowners and could be done on the minimum;
tripped GFCI, broken off light bub in the socket, noisy vent fan, tripped overload in disposal or wall heater, and to many plug in space heaters on a circuit.
The policy would not cover much more than the minimum, a few times I tried to bill them for a panel change out and it was lots of extra paperwork, I have no idea what the policy cost.
When our rates went up one time we lost the contract, but then some of the homeowners continued to call us and just pay us, so I think the policy was worthless.