| You should always charge tax whenever required to do so by the State Law! Furthermore, you have to report your sales tax collected in the event that you are required to collect sales taxes from your various jobs. These can be electronically filed, discuss with your CPA and he will assist you with this effort.
I think the best way forward for you is to let your client provide you an 1099-Misc net of all your direct expenses. It will reduce the amount included on the 1099 Misc/
You would pay regular income taxes on the amounts from your 1099-Misc, but, in addition you would also have to pay Self-Employment taxes on this amount in the amount of 15.3%. | 
