We stayed at Elena's place for one week after Christmas. It is a delightful apartment in a good location - a quiet neighborhood which is still very convenient to the downtown area.There are a few restaurants and a Carrefour express right outside the door, but it is a four-minute walk to a busy street with a grocery, tram stops, restaurants etc. We used the trams since the metro was more like a 10-minute walk. But the trams will take you right to the Duomo where you can transfer to the metro.
It is located on the top floors of a classy old building. Elena has done a wonderful job decorating it - I thought she must be an interior designer. There was plenty of room for 5 of us with two bedrooms in the attic and one bed in the study downstairs. The double bed was very high quality (I don't there is also a spacious dining room and living room. You could fit in even more people although there is only one bathroom.
We didn't meet Elena in person but her friend let us in. Elena however was always available to answer questions, give advice on restaurants, travel, etc.
The only problems I would mention would be getting upstairs might be difficult for some people - you have to bend back a bit to clear the ceiling. And if you have trouble climbing stairs then you might think twice since it is on the top floor with no elevator. There was not a shower curtain when we stayed there, so you have to shower sitting down which was not very pleasant. But otherwise you should feel confident in booking this apartment!