When installing PVC coated conduits, can we charge for repair for damaged coating? Thanks
If it's due to your installation methods or failure to store and handle properly, then no. There are a lot of ways to mishandle this product during installation.
If it's due to another trade trashing your installation, then technically yes. I say technically because unless you carefully document the condition of every stick and fitting you install, even if you identify the culprit, it will devolve into a he-said she-said contest.
If you want to carry an internal cost because you know from experience your crew will do "X" amount of damage, that's fine. As others have pointed out, more experienced crews may carry lower internal costs. I wouldn't carry anything in the estimate for outsiders damaging things, unless you expect unrecoverable costs. In any event, you certainly don't want to make it a line item in the estimate you transmit to the client.