This was a solid apartment in a good location for walking or taking the metro to many points in the city. Las Ramblas is not that interesting itself (even more touristy than the rest of the city), but it is an easy walk to many other neighborhoods. It is also in between the orange and green metro lines, giving good access to points farther out in the city.
The apartment itself was simple but seemed to have good amenities. We were hardly there, and just used a few of them (mainly the kettle, fridge, and some dishes).
The entrance was definitely as described - a narrow staircase and climb of several flights of stairs, which was a little difficult for my older mother with our luggage, but was also quite memorable.
There were two keys for the apartment, which was nice so that we could split up more easily. When you check in, you will get access to an app that allows you to unlock the door from the street, but there is also a normal keypad, which is what we used most of the time.