They call me and have me repair their auto shop equipment I also have estimates that were given and ok'd to go forward and order parts and they were never altered afterwards the prices given are the prices they were charged. Also the terms are stated due upon receipt these receipts were signed. I also have emails stating payments are past due and I also have text messages these invoices would be paid. The customer did pay for jobs on one location that his son runs but none of the other shops I did work at were paid. Its amazing this person is in business let alone about 20 locations. I cant believe he has any servicer willing to do work for him.
The definitional subchapter of the NJ Prompt Payment Act (the "PPA") limits eiligible claimants to those who "improve real property." See https://law.justia.com/codes/new-jersey/2009/title-2a/2a-30a/2a-30a-1/.
If the equipment that you repaired is a fixture to the property (i.e. it cannot be easily removed and reinstalled at another property if the owner wished), you would be entitled to argue that the owner is liable under the PPA. The owner will likely counter that it was just a service contract for equipment (and NOT work which improved the value of the underlying property), but the answer would be determined by the nature of the repairs which you performed.