Should I close and open the building's door every time I want to exit, if some of its residents possess ill-gotten wealth, out of piety?

This action is not an act of piety (wara'). Piety is abstaining from doubtful matters for fear of falling into forbidden ones. The presence of something unlawful in a person's wealth has no relation to the open door, and your closing and opening of the door is not an act of piety.