Hi guys... I just bought a place in the city in a highrise building... We moved some stuff in the other day and a guy came to our apartment shortly after looking for the former tenant (who hasn't lived there for years---he foreclosed). so, we sent him away but he looked a little weird, but he claimed to be a private investigator... in our bldg it is well known that this guy had A LOT of overdue bills, collections, and probably even court dates for his non-payment issues... right now our consierge is being scolded for letting the unsavory character in, but our concern is to whether this guy was a bill collector or a real life loan shark....or working for one (since we both doubted he was a PI). ~~WEIRD~~
It is rare for a bill collector to come to your home, but it has been done (and when I was a collector I did it).
It could also be a PI trying to track him down if there is some serious action, such as back child support or something. In that case the ex might have hired a PI to help find him so she could serve him papers. I have a friend who is a PI and he does this kind of thing more than you would think. If it's a large amount of money, it may be worth hiring a PI to find the person, maybe where they work, etc.