We run a credit report and background check are you ok with that?

Credit reports and background checks are very common in the trades, especially if the hiring company has a strong focus on residential plumbing and/or need you to be bonded.

If you have a strong credit report and clean background check there is nothing to worry about. (One single credit check will not dock you major credit points as many believe to be true.)

You could reply briefly such as: "I am absolutely okay with that. My credit and criminal background are clean."

If you have a bit of a marked past or poor credit now is the time to openly disclose that.