Eleni's place is definitely a hidden gem!
It is homey and roomy; with two bedrooms, a living room (that can be closed off from the kitchen, if need be), a full size kitchen, a washing machine, ACs, super comfy beds, etc. The place was perfect for my week-long stay, but it will work just as well for longer stays. The place is very quiet, so I could work throughout the day and sleep at night. The nearby neighborhood has it all - restaurants, pubs, grocery, a fishmonger, an excellent butcher and a super fresh produce store. There are local theaters, which I didn't have a chance to check out, and local boutiques.
Athens center is 15 minutes away by car. I took the train in several times, and it was a pretty quick trip. Kypseli neighborhood is not touristy. It has nice parks and squares, and there's a spectacular, very affordable massage/physiotherapy place (Know How Massage) about a 10 minute walk away from the apartment.
As far as hospitality goes, two lovely ladies (Eleni and her sister) welcomed my husband and I upon our arrival. We very much appreciated the conversation and the fresh fruit, coffee, etc.
Interactions with Tasos who co-hosts with Eleni were lightning fast and always pleasant. The hosts are kind, thoughtful, and accommodating offering the kind of hospitality that makes one want to come back!