When they pay with gratitude and respect for the project instead of money.

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Oh wow! Look at all the food and bills I can pay with all those gratitude and respect!

No-one ever pays for a project with gratitude and respect instead of money. If you think they're doing that, said gratitude and respect is fake and should be immediately returned.

However, I've had plenty of projects paid with gratitude and respect *as well* as money. Said gratitude and respect in that case is much less likely to be fake, so in that scenario I'll accept it ;)

I have a client who I’ve worked with for about 5 years off and on. He’s great! This latest project he paid 100% of the estimate in advance even though certain circumstances (death in the family and other issues) have prevented him from moving forward on the deadlines. Most clients would ask for a refund but he hasn’t. And he shells out lots of praise and gratitude with every deliverable I hand him. I wish all my clients were like him.