We stayed at Erol's place (it is a hotel actually) for 3 nights. Photos are accurate, staff is great, amenities and internet connection is very good. The location is good. It is close to everything in Taksim/Beyoglu area and Taksim & Sishane metro stations. However, due to its proximity to night life and location by a main road, it was little hectic outside and there was A LOT OF NOISE coming from the road (Turkish drivers love to use their honks for anything) and more importantly, every night until around 4am in the morning, there was loud music sound coming from somewhere they couldn't locate. We were able to block the street noise with earplugs, however there was nothing to do about the deep bass sound of this club. We could hear every song clearly and it ruined our stay in Istanbul; NO SLEEP FOR 3 NIGHTS!
Once they find the source of this night club music, report it to the police (it is against the law to play such loud music after a certain time in Istanbul but nobody seems to care about it) and follow up, I think this place will be a good value for the money you pay. Until that is resolved, I don't think I would stay at Erol's place again.