From another member who is unable to post on this forum:

“The foundation for the steel structure quoted by Allied, and one that was omitted, Empire based in San Diego, IMHO was the lowest and best option with 30’ spacing on posts is 12” X 30” sauna tube concrete footing, called out by their company engineering , to California building code standard. Jai pal Khalsa is incorrect about the cost and design of the foundation. It’s nowhere near the > $20K he claims it would cost for the CSS to excavate and pour 8 -10 post base footings. A 10 yard truck is $1200 , short load mix on-site is $120/yard times around 1 yard per footing.”