In my state labor on fabrication of tangible personal property is taxable, so are a few other services. But most labor is not taxed.

We have to charge sales tax on our labor (installation of glass on automobiles, residential & commercial property).

To be safe I'd check it out with your state, you should be able to look it up online.

And I can't believe your accountant charges you for questions like either. We've had a couple in the last 5 years & none would even think about charging for something like that.