Would it be possible to implement a graphic for each house/property which shows a timeline of who has lived there, and for how long?
I'm thinking something like the standardised timelines used for band line-ups on Wikipedia, where it shows members coming and going, and the instrument they play. Here is an example: https://en.wikipedia.org/wiki/Paul_McCartney_and_Wings#Personnel
Instead of instruments the key could show whether the person was the owner, tenant, lodger, etc...