I think if you're planning on living there for 20+y then buying pays off. In the central districts (the first 9), it's hard to find apartments under 250-300k, but I wouldn't be scared of living a bit further away from the central area. Vienna has excellent public transportation which guarantees you that you'll get from any point A to any point B within 30-40mins, which I think is quite a good deal. (Considering traffic in the central areas I wouldn't think you'd be able to save much more time.) I'd go for it, Vienna is one of the best places on earth to settle down!