Basically it's a single room accommodation right at the famous sunset spot of Oia. It was simple, clean and nicely located (but you should know that there are lots of people walking along).
Santorini and esp. Oia are unbeliebveably expensive so Agapi's house was quite a deal (although in my opinion not worth the price but this is Oia...deal with it or don't visit Santorini).
The communication was quick and friendly but we have not met Agapi. If you expect to live there with locals giving you tips for exploring the island, this is not for you ;)