Nice place for a short stay. Good location, quiet area nearby the lively part of Beyoglu, unique design. Only cons is it's a little small (cozy for 2 people working) and we had some issue with the shower water heat - didn't get hot water. Wasn't a big deal for a short stay but could be a problem if you are there for longer. The entertainment system was a nice touch if you want to stay in and chill.
The host was extremely friendly and communicative. Would definitely stay again if I was returning to Istanbul for a short period.