This is not entirely accurate
I realize this could vary from state to state, but it's not a double taxation of any kind
The contractor pays the Sales And Use Tax on the materials, as the contractor is considered the Consumer/User
If the contractor passes along the cost of the Sales And Use Tax to his/her client, there is no "double" taxation
However, if you are listing your materials separately, and "collecting" Sales And Use Tax on them, and not handing that money over to the state, you could have issues with the state
In that case you should have a resellers permit and not pay Sales And Use tax on the items in the first place
But in any state I've worked in, the contractor is considered the end user, and can absolutely collect from the customers for what the paint supplier collected from him/her for the state on the materials purchase
The invoice would read
Materials: $11
Rather than
Materials: $10
State Sales Tax: $1
Total: $11
