Adding my voice to this URGENT request for Invoice Tipping!  I first spoke to Quickbooks about the need for a customer tipping "prompt" back in 2014, and at least 2 other times in the intervening years.  I have most likely lost out on hundreds, if not thousands of dollars worth of tip income during the past 7+ years that I have used Quickbooks.  Needless to say, this issue is way past due for being addressed.  Back in 2014, I got the same reply that is shown in this thread:  "We will send this feedback to our development team".  Baloney!  I can't believe there is still no option for a customer to be prompted to add a tip to an invoiced amount.  If I wasn't so invested in my QB record-keeping, I would love to change providers!  Please, Please fix this issue NOW!