HELP first time buyer! Buldge in fiberglass exterior wall

Like others said, RUN !!!!!! But if you choose not to, be aware that it will be VERY hard to sell in the future. They might not even take it on a trade in or if they do give you next to nothing for it. That's an EXPENSIVE fix. BTW, it's not always caused by a leak, this is common in the Northeast, due to the moisture of the heating and cooling of early winter and late winter.