What I did not appreciate, but they did, is that these rails can bring an absolutely astonishing amount of noise into a town, and behind that a long trail of associated social ills. There is a gradual sifting of residents within a certain distance of these trains, based on who is either loud themselves and thus doesn't mind, or else must tolerate the amount of noise these things make.
Our town is old enough that some of the 'nicer' neighborhoods predate the introduction of the rails, so there isn't a strong confounding signal of 'bad' neighborhood correlation at work here. In at least one case there was a house we pushed past our agent's scheduling machinations to see for ourselves, and would likely have closed on had we not happened to visit at just the right time, when a multi-engined repositioning train (which we had no idea was a very common guest on what we thought was a mild mannered commuter rail line) came through. Though unseen and multiple blocks away, it still shook the floorboards as it passed.