The apartment is in a great location, well set up and meticulously clean. The photos are an accurate depiction.
Devrim, the host, was very kind and checked in regularly to make sure I had everything I need and was always ready to help.
It is readily accessible on public transport and a short, comfortable walk from Tophane (manageable, with luggage). But it should be noted that there are steep inclines if you are approaching from Taksim and some other directions - but that is typical of the neighbourhood.
The building has a lift and there is one apartment per floor, so there is a lot of privacy.
I already feel that this will be my home away from home whenever in Istanbul. Thank you, Devrim.