Sokol's place is a god choice for someone wanting to stay within a 10-minute walk of the city center (specifically Monastiraki). Warning - the location is in a bit of a rougher area than I was expecting - nothing severe but as a younger woman I was cautious. However, the building itself is very secure - the front door and every room is locked, requiring a code or key.
The apartment itself is small but pleasant and has all the basic items you would need. I would recommend it to single and double travelers who don't plan on being in the apartment much but want a cozy spot to return to. Sokol is also very communicative. He gave excellent instructions for getting into the apartment and checked with me throughout the week to see if I needed anything.