The apartment was excellent. Room was very clean and was in the ground floor facing away from the sun so there was no need for AC. Dan was a great host and helped me out with a medical emergency as well as laundry. Location was stellar with the closest metro across the bridge from the main old town by less than 400 m?

Only gripe I had was that during my stay, the building had construction so in the morning ~7 AM, there would be jackhammers going off so there was no chance to sleeping in if you needed to.

All in all, very good experience and would stay at Dan's apartment again if I ever go back to Vienna.