I was able to use my credit card to put a nice sized down payment on a car, with a simple call to my bank. I have no idea what the limit to that exception process is. (Collected huge cash back, and paid it immediately with money I had set aside for the car so no interest)

But what about the clearance process? Different ways the money comes in would take different amounts of time to clear, all more than 24 h, so if we have to worry about that, the bank probably won’t let us spend more than we already had