In 2004 I actually got to wander around 1A when I visited KP. My sister and I were in the State apartments and couldn't believe when the tour then led us into 1A. Princess Margarets apartment wasn't being used for anything at that point and so it was open to visitors. I remember we started at the top of the house and were able to look in a couple of bedrooms. On the landing you could look out the window and see directly across the courtyard to the Michaels and Diana's old apartment. We were literally looking at their front doors. There was a lift in the landing but we took the stairs down and there we were in the black and white slabbed hall behind the big wooden front doors. The door to the blue drawing room was open but there was a rope so you couldn't actually walk in and at the end if the drawing room there were double doors that opened into the dining room and they were open too so we could see a bit of the dining room too. We then walked behind the drawing room to a room where PM kept her china and you could look right out the window there into her big private garden. I couldn't believe at the time that I was getting to walk around PM's actual house, I kept thinking of all the times I'd read about it in books and all the famous people who had been in there and it was totally surreal. There were pictures if PM in each room to show the visitor her standing where they were standing, just amazing. I don't' know how long the apartment was open to the public but I consider myself so lucky that I visited KP when I did. It's still hard to take in that I have been all around William and Kate's house (well some of it) before they were. The rooms BTW were of a decent size but not huge. Only the drawing room was of any considerable size.