First of all, Thanks Erkut and Emir to your help during our stay.
The appartment has formidable conditions in terms of the location, the cleanliness & equipment and the fluid communication with the hosts,
This is however not the perfect appartment to visit Istanbul with elders and a kid.
It was hard for us to walk uphill on omer hayyam street specially with the stroller and the elders. Even the taxis avoided to drop directly on the adress of the appartment but prefered to drop us at the top of the street to leave us walk down a steep slope.
The elevator also stopped working for 3 days while the appartment is in the 6th floor.
Thankfully the hosts helped us with the lugagges on check out!