"May I ask what gauge sheet metal you used and what tools you used to shape it?"
Yes you may...
I´m using 1 mm (19 gauge) galvanized sheet metal. Just because I want to be sure that I don´t have to do this never again.
My tools are very simple. Just angle grinder, shears, sheet metal folder, planishing hammer, and so on... And then there is a sheet metal roller that I can use.
I wish that some day I had an english wheel or a planishing hammer and all those professional tools. They are too expensive for me to buy, but some sunny day... Win lottery...