You negotiate a price based on (x) number of designs and (x) number of modifications.
Otherwise the person will just keep draining you, because everyone thinks they can design, except they can't. So they dilute your work to the point that it's a terrible mess if you give them a chance.
Otherwise the person will just keep draining you, because everyone thinks they can design, except they can't. So they dilute your work to the point that it's a terrible mess if you give them a chance.