Adding a Lean-to on the side of a building. Anyone know of a good kit?

I have two. First I built from lumber with a metal roof attached to my 24ft shop. The 2nd is an 14ft aluminum patio kit from patiokitsdirect online out of Corona CA. They ship everywhere and it is rated for snow load. I think a pole barn building supply would be the most cost effective solution. I just priced a new shop from them.