I have copper pipes in most all places. They suggested replacing the copper in the walls with the pex and have half and half (as in the pic) or pex everywhere. I thought keeping the copper under the house since it isn't a thing rats chew through (I have pest control but the house is in a neighborhood where neighbors have massive rodent problems). The copper pipes were installed in 1977. What do you think? Think the copper is cool to keep under the house and put pex in the walls or do you think I even need to replace the copper in the wall at all if it's still in good condition? He was saying that since it was installed in 1977 it is likely coming to its life

https://preview.redd.it/i9z2vw9nxecd1.jpg?width=1532&format=pjpg&auto=webp&s=52fb1eff3eb19c86d891d1ee05b56db6d4a7e211