A concrete pool is so much more substantial and so much higher quality than a vinyl liner pool that it seldom makes sense financially for the value of the property to convert a concrete pool to a vinyl pool.
Convert vinyl liner pool to concrete.
It is very easy to change your existing pool into a concrete gunite pool.
With this option you can shallow or deepen the pool.
The vinyl liner conversion process.
Last but not least you can just change out the liner to give you another 10 to 15 years.
To convert your vinyl liner pool into a one piece fiberglass swimming pool that will actually be ten times as strong as a one piece fiberglass pool insert and seventeen times more flexural strength than a concrete.
Pour a concrete base if necessary.
If just want to change your pool completely you have a couple of other options.
Remove the existing liner and haul it away.
Install or reconnect floor plumbing for main drains.