Customer was having issues with the sink draining in the hallway bathroom, so I ended up running my cable down the line and removed some hair, but it was also a lot of rust due to having cast-iron, customer just moved in and the entire house is cast-iron drain pipes. I let the customer know I think the main issue is the cast-iron rust that’s catching the hair. I was able to get the sink draining again after testing it with no leaks and no backups. We have a camera tech coming out to inspect the drain pipe and leave options to replace the cast-iron.