I've had the misfortune to be present for an in-person demo of a verification service nearly a decade ago. It involved those relationship questions ("Which one of the following people have you not lived with in the last 5 years?") that are incredibly creepy. I was shocked that they had so much data on me -- I have no debt, no credit cards, no house, no car, no bills, and I had always entered informal rent agreements…
Temporary postal mail forewards. USPS NCOA (Change of Address) file is another major data source. https://www.forbes.com/sites/adamtanner/2013/07/08/how-the-p...
"There is, however, a loophole that keeps data brokers from accessing your updated address. When you fill out the online form to change an address, you can indicate a temporary change that provides six months of forwarding that can then be extended for another six months. That information, unlike the changes marked as permanent, is not included in the master list sold to data brokers."
And the online link for online change of address with the loophole:
https://moversguide.usps.com/icoa/home/icoa-main-flow.do?exe...