We really enjoyed our stay at Lisa and Karl's place in Stockholm. The place is very well situated, close to the metro station and in a beautiful area of the city. You can be at the Central Station in 5 minutes and Gamla Stan is only another stop from that. So you can't beat this.
It is a beautiful flat, very clean and well decorated. You have all you need to cook in a compact but efficient kitchen. The area is quiet. You can hear the neighbours across the courtyard at night, but I found it added to the charm.
We never got to meet Lisa and Karl - they had a friend meet us to show us around - but they always responded quickly when we had questions.
I highly recommend a stay at Lisa and Karl's.