This is an excellent place. We got a 2 bedroom for a longer stay and had no complaints throughout.
It is an excellent location near all trams and walkable to center of istanbul. There is a co-working space a few mins away if you are looking to get some work done.
There's restaurants open from early morning to late at night nearby.
It's a quiet street but 1 min away from all the hustle of Pera and Istiklal street.
One tip for people using the tramway from karakoy is to take the tunnel up and down (tunnel tram station is a minute walk away)
They have cleaning service every 2 days which we did not expect and we're pleasantly surprised.