My wife did this, about 6 months of digging up roads in central London. Would recommend. AMA.
Low hundreds of homes (so low probability that you know anyone there, and if you do they have already heard about it).
What were the returns - time will tell, but I probably have the best internet in London
What do we peer into - 10Gbps of NTT, two more 1 Gbps full peering sessions, plus the LONAP internet exchange to pick up Google, Netflix, etc. Plus my wife (AS210412) peers with me (AS211289) of course.
Also some bias shows here - surely the question should be ‘how did you meet your wife with multiple 3 ton excavators’.