It could be an Austro-Fiat, but it has already been establish that it is "a little older than 1927". According to Wikipedia, Österreichische Automobil-Fabrik, previously known as Österreichische Austro-Fiat, began production of their own cars in 1925 when the Fiat license expired. I think the puzzle car could be an early OAF, and, although I don't have a model number, I will try an OAF Pullman Limousine from about 1925/1926.