Petra's place is right off of the main street in a quiet part of the Mala Strana, just a short walk up to Prague Castle and St. Vitus Cathedral, and the Hellichova and Malostranske namesti tram stops. It's a historical building, so it doesn't come with an elevator - so people with large luggage, please take note.
Otherwise, this place was everything we wanted and more! Petra's daily breakfasts are amazing; I really liked trying all the different Czech specialties, like their pate and plum jam and cheese. My new favorite drink is lemon balm tea in the mornings; and my new favorite activity in the morning is watching Petra's companions, Bina and Mina (cats) and her adorable dog Bershka. The antique furniture around the apartment gave it an even more upscale vibe.
With three people (two girls and a guy), we had an extra pullout bed in the corner with just enough room for all of us. Both beds were very comfy, and we could turn the heater on at night to ensure we wouldn't be cold. There are extra blankets and towels provided anyhow.
One of our favorite parts was all the tourist information Petra had gathered and stored for us in the desk! Very helpful in deciding where to go and what to eat when all of it is already laid out in pictures for us!
I would definitely stay here again when I'm in Prague!