There is no taxable sale of a good or service.So what? The FairTax doesn't tax sales, it taxes "gross payments for the taxable property or service." "The term 'gross payments' means payments for taxable property or services, including Federal taxes imposed by this title."
That's what a sale is - the buying of an item at its price plus the FairTax. A sale is a sale is a sale - not matter your obfuscation attempt.
What taxable property or service is being sold?
What is being purchased to tax?
Nothing. The "fairtax" is zero on gov't wages. It is a special rule implemented that creates the tax on gov't wages, not a sales tax. Without the rule, gov't would be able to grow by hiring employees for much less than contracting to private enterprise.
Hence the price (including the "fairtax" of zero if you like) is 23% of the wages.