Is $30,000 to install a new vinyl pool liner a fair price?

I'm looking for advice on finding pool leaks in my vinyl liner. I've had issues with previous attempts to fix leaks; one company applied thin raft material patches for $800 that fell off, and another suggested a professional diver for shallow water, which I found questionable as a scuba-certified instructor. I've also had a company use sonar equipment. I'm seeing bulges around the pool walls and the pool can't hold water past a certain seam. I'm concerned water is going into the ground under the stone. I'm trying to get one more season out of the pool while I'm redoing other parts of my house. I'm looking for advice before I potentially pay another $2,000 for patches.