Maybe human ...
But there are others living inside Baldur's Gate.

Elves, Gnomes, Dwarves, Halflings ...
Not sure about the last one, but the others are living at least thrice as long as humans ... also character creator is not even yet complete, as we were told by Swen there will be more options in full release and since we CAN create white haired characters, its quite possible that there will be possibility to create mid-aged human at least.
I see no relation to if capable person will or will not be noticed by Duke ...
For one, even him was kidnapped by the cult ... and for two, we are talking here about if someone with Urchin backstory can possibly own the same house as a Noble ... and i say they deffinietly can.