Nick is a great host, taking care that guests are well informed, met and greeted in time, and that they have all they need. He will provide you with all info you might need on the neighborhood, maps, a complementary bottle of water in the room, and his assistance whenever you might need it. The apartment is in a quiet and safe street, which is on a very good location. The room itself is very neat, clean and bright. I appreciated very nice private bathroom that had everything you might need. Nick provides towels and toiletries, which comes in very handy, so you don't need to bother with bottles. The bedroom is facing inner backyard, which is making it very nice to sleep in a comfortable bed- it is quiet and you cannot hear outside traffic and noise. Very rare in cities nowadays.
The neighborhood is very nice, with several cafés, a good bakery and a restaurant that Nick recommended- do have lunch or dinner there. There is a corner shop and a larger supermarket just two minutes away.
National Gardens are few minutes away on foot, from where you can easily reach Syntagma square, Plaka, or on the other part Kolonaki with Benaki and Cycladic Arts Museums.
If you like walking, you can get on foot pretty much everywhere in central Athens. I did not use public transport, but you might want to know that metro station Evangelismos is also very close.
All in all, I am very happy with my stay at Nick's, and would definitely return.