I am a UX/UI designer and started communicating with a potential client for designing a mobile application. We have initially agreed to start with the logo:

Me: Hey! I haven’t received any update from your side for the past few days. Can you please share feedback on the logo samples I’ve sent you?

Client: HI, thanks for the message! Yeah I saw them and they’re great. Very simple and clean designs. We’re going to move forward with our designs now assuming we’re going to use the logo, but that may change. I’ll let you know if we decide to go a different direction, or if we need a final version.

ME: Okay, no problem. I will send you an invoice for the work done so far.

Client: Invoice? Do we really need that, or should I just send you $25?

Me: That’s not really enough. I’ve spent several hours working on this already, which would total $X.

Client: What? I thought you were doing this as a passion project!

Source: Clients from Hell