I’ve seen some resources floating around including, if I’m not mistaken, a spreadsheet that adds up all the costs of everything you need.
Basically I want to create an internet coop that’s resistant to internet shutdowns and can keep running in situations where the wider internet is shut down but we still have electricity.
If you aren’t looking to use one of the many alternatives others suggested and want to do something traditional, look at SandyNet in Oregon and US Internet in Minnesota. Especially the former, since Sandy is a lot smaller. They’re locally created fiber networks, the former being city run, that eventually expanded into full offerings competing or replacing Xfinity, etc.
I remember posts on Reddit years ago asking similar questions too and there was one from somebody who was putting satellites on their neighbors houses and sharing their Internet that way. It was more piggybacking off of an existing ISPs business class service though, I believe. So not as resilient against downtime.