What is the average price per square foot for tile installation in New England?

I pay my subcontract installers $5 per foot on if over 100 sq foot. They provide labor, all tools, thinset and clean up. They must be insured for $250k. (located in CT. would vary by area I'd guess)

Keep in mind that is the price for a contractor paying a sub contractor. I tack my profit on top of that.

Any other work such as adding a layer of subfloor is extra.