Getting off topic, but somewhat relevant: if your customer offers you payment, take it! If the cost of that payment method breaks the budget, price it in.
At the first place I worked out of school they were sometimes thrifty and other times just cheap. Places that had a discount for prompt payment instead of the full NET30 got paid fast, but if they missed that window it was the “when we get to it” pile.
One of our shops in Indianapolis did a lot of walk in work for us. Run the intern or junior engineer over, let them watch and learn, get parts in a couple hours. I was lucky enough to be that intern then engineer. Often the owner would greet us by nervously asking if we’d gotten his invoices, and if anything was missing. Makes sense now that he wouldn’t want more work if we weren’t paying for any of it. I’d been told to keep him happy, so I’d honestly offer him the company credit card on the spot both for that day’s work and for any past due items. I don’t think he ever accepted, and I’ll bet he lost more than 3% in stress, extra phone calls, and opportunity cost waiting for our check to eventually arrive. Really a pity because I learned a lot from that guy, even if some of it didn’t sink in until a few years later.