Phillip Jeffries, Schumacher, Thibaut, Cole & Son, de Gournay, Gracie, Farrow & Ball, Morris & Co, and the print-on-demand houses each publish their own hanging instructions, and they differ: paste-the-wall or paste-the-back, double-cut or overlap, reverse-hang or not, which primer, which adhesive. We keep the manufacturer's instructions on the job and follow them, so the product warranty stands and the room looks like the sample.
We'll also tell you when a specified product and a substrate won't get along — grasscloth in a steam shower, peel-and-stick on knockdown — before the client has paid for it.