if you are looking for a standard, hotel room imitation, modern accommodation avoid contacting Peter! The real house museum of Edimburgh: the largest collection of tea and infusions I have never seen, many many dvds, one real singing piano, photos, postcards, pictures, books and a lot of others objects. Also some specialities for your breakfast made available by the kind host.
The flat is 30 min walkiing distance from Waverley station and Princess street, anyhow the bus stop is near and buses run since early in the morning, till late in the night. There are several shops and restaurants in te neighborhood, some of them are even suggested and described by Peter in a short and helpful tourist guide he gave us.
In general we had a good experience: prepare to be a little bit adaptive in case of more then 2 guests; be ready to dive in the authentic and original Scottish atmosphere