Katies place is highly recommended when you wish to explore Edinburgh for a couple of days. Only 15 minutes from the castle and the Royal Mile on foot.
The apartment is very comfortable, fully equipped and very clean. We immediately felt at home. Directions given upfront by Katie were very clear.
We parked our car at Qpark Simpson Loan a 7 minutes walk. It is quite expensive, but secure. Book in advance, it saved us 6 pounds in the end.