If you’ve received an offer to start a new job, remember that that offer is just that—an offer. So, think of it like a suggestion or an idea. You are not obligated to accept that very offer. There’s always more money they can give you. Keep in mind, too, that they don’t want to go back into interviewing candidates. They like you. You have wiggle room to ask for more.
Know when to shut up and you might just win the argument.