JoeBart:
I find it best to give a "written estimate" to the customer, prior to doing the work. This helps to prevent "misunderstandings", and keeps you "legal" with the Board. (You're in NJ). CCheck within the Laws & Regs booklet you received with your Lic. & Business Permit. Without going into all the legalities here, if you play by the "rules" you have a better chance getting compensation if you go to collection or small claims court.
T&M work we bill with an excel spreadsheet, and QB invoicing.
We track all jobs with excel spreadsheets.
PS: I'm in NJ also.If you need further info, you can e-mail me direct, or continue thru ECN
John


John