Grocery stores and convenience stores not only sell food products, they also sell a wide variety of other items and services – some of them taxable, and others nontaxable. For example, flour, sugar, bread, milk, eggs, fruits, vegetables and similar groceries (food products) are not subject to Texas sales and use tax.
If your customer provides the materials, then you are providing labor only. You're not responsible for tax on the materials. Under a lump-sum contract, you do not collect sales tax on materials or labor from your customer. You are the consumer of all items purchased to perform the work.
Contractor services performed on residential real property are not usually subject to sales tax. The Texas Administrative Code Section 3.291(a)(12) defines residential real property to include the following: Family dwellings. Housing complexes.