Sale Flag Sign

We are having laminate flooring installed next week. The distributor itemized costs on a sheet of paper, all of which appeared reasonable on initial inspection (square footage x unit cost of flooring & sound/barrier combo, labor, trim extras and a total that reflected a sales tax of about 7.75%).

Upon signing the initial agreement and putting down ten percent it was brought to my attention by a colleague that sales tax should not have been assessed on the labor. Given that this would be about a $400 swing in my favor, I thought to look up relevant California tax and contractor laws. I didn't find anything on-point.

Can someone point me to the relevant statutes that address this matter, for or against?

As an aside, my colleague said all the distributors up and down this street are notorious for charging tax on labor when they shouldn't. The fact that the costs were not itemized on the signed form could be a red flag to that point.

Thanks for the info.