Sewer Backing Up Into Basement

Like a lot of people after the recent storms in the Midwest, we had sanitary sewer backup into our basement. It flooded out our water heater and spread filth over the basement floor. Our homeowners insurance isn’t going to pay out anything. We called a plumber who said they could install a backflow preventer valve but it’s going to involve digging up the yard and it’s going to cost a fortune. How much should this kind of job cost and are there any other options? We can’t keep having filth flood our house.