Actually, Andrew, Amman is not visually obvious; one can easily walk past buildings such as this one and barely take notice. The city has loads of character but it takes a little experience getting to know where to look.
This particular place was successively a house, a post office and a hotel. Mamdouh turned it into a Diwan, a guest house, in 2001. Anyone can walk in, have tea, read the papers, relax and chat to whoever happens to be there. Its also a venue for book signings and activities with environmental or conservation themes. For online searches, look under dukes diwan.