first of all buying an old/abandoned village with friends vs "this piece of jungle will become a city" is a slightly different scale of a problem.

villages have infrastructure, sure they might be tied to municipal grid but it was a place where people live(d) so it tends to have water and power in one way or the other. depending on the geographical location residential solar can solve a lot of power needs in the mid term (provided you're in a reasonably sunny climate).

the suggestion of building a nuclear power plant for the purpose of a group of friends starting a community somewhere is obnoxious. obviously it would be great to have an abundant energy source, but that being prerequisite makes all of these plans a armchair survivalists dream.

the citadel doesn't need to sustain itself or attract people, the community can first prioritize food independence which is not impossible to achieve with decent amount of land over couple of years, while building out the infrastructure for other things on the go. the point is not to create an isolationist dream setup (thats how everything fails), but a community of productive families that work towards greater independence