Epoxy lining is a possibility but it's not an ultimate solution to all your piping problems. We had this question before here
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and elsewhere on the site, and I would have to say that to the best of my knowledge the amount of good experiences is about the same as the amount of bad. Is there really something that completely prohibits replacement of the pipes in question? Like, historical home, multi-tenant, multi-story and other situations when the pipes are absolutely inaccessible or create unsurmountable hassle when walls are open? That's when the epoxy lining of existing pipes will be at its best.
It is not often justifiable in your typical 1-2 story wood/drywall construction residential house. At the end of the day consider that you will still have old pipes even if lining worked flawlessly.