Ondrej's apartment was pretty amazing. It was super safe. Location to the main tourist destinations couldn't be better. You're in the middle of it all but tucked into an old building behind 3 locked doors. The cafe downstairs serves superb coffee and breakfast with a very friendly staff. All in all, you couldn't get a more authentic experience. The only downside is the smell of cigarettes from the floors below. But if you know Prague you know this is virtually unavoidable. Just something to be aware of for people with delicate sensibilities. I highly recommend this place.