I have a client who in the past paid his invoice either on the due date or a few days late. They have also told me they have cashflow problems (big red flag right there).
Client: For the next project, we would like to have longer payment terms. We don't understand the problem. We have clients of our own that pay only after 3 months.
Me: My company is just me and I need to be able to pay my bills, too. I expect clients to pay their invoices on time.
Client: If I knew you were living on bread and water, I would consider paying you earlier.
Wow, that went non-professional real fast! "Why should I pay you if you aren't starving?"