Was my joint cased?

I should probably preface this post with some information. First, I live in a house commonly called a double shotgun. Basically its one house, with two seperate apartments/homes side by side. Since I moved into my current house there has been a leak from the roof into Sebastian's bedroom. After repeated attempts by the landlord's handy man (who lives on the other side of my double shotgun) the leak is still there. So yesterday an african american gentleman, whom I've never seen prior, knocks on the door asking which room has the leak. So he is escorted to Sebastian's room, we show him where the water is coming through. He proceeds to the roof where he goes to work fixing the leak (I assumed).

Today our handy man Mike asks me if I had called a roofer to take a look at the leak in my roof. I reply no, I assume Eshyah, the landlord, made the call. As it turns out, nobody seems to have called anyone to look at my roof. Nobody has paid anyone for work that was done. The landlord, myself and the Mike have no idea who he was or why he was actually on the property.

So what possibly could be the explanation? Was this actually someone casing my house, knowing many houses in New Orleans leak because of their tremendous age and using it to gain access and confidence of the occupants (me)? I wonder if the roof was actually fixed, the next major rainfall will let me know I suppose. Should I be worried, install an alarm. . . get a guard dog?

What would you do? Can you explain the case of the roof repair guy? He was never called, never paid, yet he was there.... Inquiring minds want to know!