We stayed for over 3 months in this flat. It has a number of favorable features - most importantly its location, which is a short walk to the Bruselská tramvaj stop on Bělehraská, a wonderful area in Vinohrady. The flat is also a loft, which means it has quite a bit of space (though not much privacy) and wonderful light. The place has lots of quirky decorations which are pretty nice. The beds were comfortable, and it was fairly quiet in terms of noise from neighbors (the opposite loft flat is also an airbnb or some short rental, and though there were parties there, the noise wasn't too bad in our flat).
The downsides are significant though: the main hallway lights often do not work, and the common space stairwell is pretty grotty and run-down - the flats below are obviously charge far, far, far less than do the Airbnb loft flats. As others say, it is on the fifth floor (sixth floor by US counting), which is a long hike when there is no elevator, as others have noted. The buildings around it have elevators, but this particular building is pretty run-down and under-invested overall. People with mobility issues DEFINITELY should avoid this place, not only because of the number of floors to climb, but because of the weird staircase/bookshelf to get to the loft bedroom. The steps are big and there is no side railing, so if you have balance or mobility issues, that is quite possibly a health hazard (we never fell off, but came close a couple of times at night). The kitchen is okay but kind of run down - the refrigerator is old and doesn't really cool things before 8-10 degrees, and there is no microwave. That said, there are plenty of plates/silverware/cooking items, and the stove top works well (electric); the oven works okay, though the outside door gets scarily hot. The toilet room is very narrow and small, and is separate from the bathroom, which has a big lovely sink but a weird-shaped corner shower/bathtub that does not function great as either a shower or a bathtub. There's not much cold water flow in the bathroom sink, and like the kitchen the hot water can be absolutely scalding unless you are careful. The floors are beautiful finished wood - the place overall LOOKS very nice - but there are (because it's a loft) a lot of giant beams that you have to either walk over or watch your head to keep from hitting it. The sky windows are great, but it took a very long time to replace the shades on them during our long stay there (one of the shades broke).
When we moved in there were beer cans and cigarette butts all of the floor and the sky window (Velux) was left open even though it was snowing and water was collecting on the floor. Apparently, the cleaner was late in coming, and we did get our cleaning fee refunded. Otherwise, the service was somewhat slow; and the hallway lights by the door still do not work properly despite raising this to the rental service numerous times. We also had to spray insect killer ourselves around the water heater, which is where wasps entered the flat.
We were committed to staying in the neighborhood, and this seemed to be the best available unit around via Airbnb when we rented it in February 2022. People trying to stay medium-term in Prague face huge expenses - too short to rent a proper flat, but Airbnb becomes simply too expensive for this kind of multi-month stay [we hope that another agency can come in to challenge Airbnb for this length of stay]. Again, the area is fantastic - one of if not the best in Prague - and we were happy to be close to so many places that we used daily. It is also very near the 6 and 11 tram stop (Pod Karlovo) and also near a Billa grocery store, which has the best prices around for food. But it was SO expensive, which I know is partly because of Prague's overheated property market (and Airbnb), but given all the obvious downsides listed above, I think we could have done better, or at least a good bit cheaper, somewhere else. But the neighborhood...fantastic!