Client: We can talk about how you would like to be paid for this endeavor. I'm open to ideas on that front.

Me: Preferably with money.

Client: Mmm, I don't have money. But just imagine how good would this project look on your portfolio!

The real question here is not "how". It's "how much" !!

@meseguer1998 Client: And once it's done, I'll give you 10% of the profits.

How is easy for me... 1/3 at contact signing, 1/3 at beginning of customer training​/configuration, remaining balance on final user acceptance. I'm not about to start sinking resources into a project unless the customer has motivation to actually see it through.

@KylePiira Plot twist: The client is a non-profit.