I wholeheartedly recommed Stavros' place! I missed my last train in the evening and was stranded in Athens train station. I messaged Stavros, he replied straight away and he arrived at the flat within 20 minutes to let me in. I'm very grateful for that. The place is a few minutes away from the train station, it's clean, beautiful and has an amazing view from a huge balcony. Would definitely come back!