So I used JOSM with a filter set to (building=yes), inverted to only show features with that tagging.

Then, I used my knowledge on how neighborhoods are usually laid out around here, to find areas with multiple features that seemed like neighborhoods. 

I used areal imagery to prove that I did, in fact, find neighborhoods, and used the lasso tool to select only the elements of the neighborhood that looked like houses.

Then I: [shift] + [e]'d to select only the ways, and not the individual nodes, and converted the tags!

This was a long, and tiring process, and even though I took good care as to select only the houses as best as possible, I might have made a few mistakes.

If you think I made a mistake or want to reach out, don't hesitate! Talk to me on Slack, through OSM Messaging, or just leave a comment here. I'm happy to explain!