Don't give them current salary. If they won't hire you, you're better off. Instead, add a (reasonable) raise to your current salary, then add another X percen

Don't give them current salary. If they won't hire you, you're better off. Instead, add a (reasonable) raise to your current salary, then add another X percentage just in case you don't get a raise for a couple years. Hand the hiring company that figure. Edit for clarity