First things first, sell the bank separately. Do not sell the account with the bank as that can only bring you headaches.
Secondly, the value of the account will be heavily weighted by how much trust the buyer has in you. If you have feedback on a marketplace, probably best to attempt to sell there.
This account is worth around $300-$800, yes, that’s a very wide margin, but it’s because it’s extremely difficult to sell accounts for high value unless you have a significant amount of trust behind your name, as the buyer just has to take a leap of faith without that trust.
Best of luck with it my man.