As advised, if members ask to cancel, I would generally just cancel and block them wihout any communication - why waste more of your time?
You now have a good idea of how much the PS4 will fetch so list it as a buy it now with immediate payment required - at least that way you won't have to wait for an auction to end again.
"There are two ways to be fooled. One is to believe what isn't true; the other is to refuse to believe what is true.”
Søren Kierkegaard, Danish philosopher (1813 - 1855)