Vaastu is usually done to maximize the efforts of a person to reap benefits. However there is no such thing called Vaastu dosh. Even if there is a water body or a drain or temple nearby nothing will change due to it’s proximity to the house, shop or factory. It is related to Karma of a person & is related to astrology. It is not about common solution for every person. It is a very time consuming, but the client must have patience when they want to do vaastu planning. But they confuse it with Vaastu consultation.
In vaastu there is no requirement for installations of any metal or any other object.