Justmy2cents is exactly right about everything he said. I other thing that you might want to keep in mind is that you have upstairs bathrooms, which means there's plumbing in the walls. I don't know in relation to were you are wallfishing but just keep that in mind. I have seen water pipes, drain pipes, sewer pipes, etc. cut and drilled before. Good luck, take your time, and charge correctly for the job. The Customer needs to pay( not just for the labor, but for the liability also) for that kind of wall fish, because if you hit something that your not suppose to and damage something the repair cost could be alot. Make sure your insurance is up to date.
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