I stayed for 3 months at Carin's house. It was a great experience living there and was it was a very nice stay. They were always open for conversations and had great tips for exploring Stockholm.
The room is in the attic but with my 185cm it was not a problem at all. The room has everything you need and is perfect for one person. The kitchen is very well equipped and you get your own space to store your food.
From the house to the central train station it takes around 40 min. (7 min to the tram and then from Alvik 30 min depending on​ where you get off). In the night time or at the weekend the tram only drives every 30min or so and then I would recommend that you take the metro to Abrahamsberg and walk from there or take a Uber (It is around 2km, It took me 20 min most of the time).
Ca 7 min away is a small supermarket, ICA, this is one of the more expensive supermarkets in Stockholm but it is fully adequate. In the summertime, you can take a swim in the lake just 10mins from the house. There also is an outdoor gym where you can exercise or just have a walk in the woods.
All in all, it was a perfect stay and I would always be there again.