Beautiful apartment near the Florenc metro stop in Prague. We had 9 people in our group, including 4 teenagers. The listing says it hosts 9, which it does, but it's a bit tight. The 4 kids could all pack up, so it was fine, but I'd say realistically you'd want no more than six or eight people if you need more space. Otherwise, it really is a nice place.
We experienced only one major problem The WiFi is 4G LTE on a small mobile hotspot. With so many people, and especially kids, the bandwidth just couldn't handle it. Also we ate up all the data for the month, so we got throttled at something like 4KB/s, meaning we couldn't use the internet at all. This became a problem because I had to do a webinar for work and simply couldn't use the internet. I had to call in instead, which fortunately was OK, but could have been a disaster otherwise. If you need internet or work remotely, then this is a deal breaker.
We experienced two small problems in the bathroom. The main bathroom shower's temperature knob was broken. They sent a plumber very quickly, which was great, but he didn't fix it. He just turned it to a temperature that my parents preferred. Hopefully they fix that! Also the tub clogged up and wouldn't drain. Otherwise, the apartment was sparkling clean. The beds were super comfy. Everything was nice.
That all said, I would definitely stay at Prague Days again!