You all are correct. I sell garden pond products and my 45mil EPDM liner with a 20year warranty will be a great deal more money. Cost will be $839 + shipping. Weight will be approximately 400#. On top of that you would want to have an underliner for about $300.
If you use the PVC keep in mind if it is not protected from UV, it will shrink 15% per year. I would also recommend using old carpet or something underneath it to protect it from the roots and rocks
Good luck!
