This is the right answer. The Freifunk people have a lot of experience and knowledge. Anecdote: A while back I was moving houses ~1km with trees obstructing li

This is the right answer. The Freifunk people have a lot of experience and knowledge. Anecdote: A while back I was moving houses ~1km with trees obstructing line-of-sight and without connectivity at the new house for the first couple of months. I had to move but could keep the old place connected. I jerry-rigged Ubiqity PtPs that I had inherited from a friend at each end. Packets started dropping on rainy days but it was working surprisingly well. Not necessarily a fan of Ubiquity and their closed ecosystem per se, and it might not be the best pick for a project like OPs if there are options. (Throwaway because these hotspots were brought from abroad..)