I have just watched the end of Mr and Mrs (Honestly, I didnt want to watch it but Doctor Who Confidential had just finished) and saw David Coulthard and his wife in the final.
She got asked a series of questions that he had to get correct when he returned from the 'booth'

One of the questions was "What is David's favourite house!" To even be asked that question is excessive!
She replied "Hmmmm. He may say Belgium, because that's where I live.... but he may say Monaco because that's where he lives. And the weather's nice, so I think he'll say Belgium!" How nice to be able to coose between Belgium and Monaco!

When He returned, he was asked the question, his answer was "Hmmm... I'd have to say the one in Switzerland, because of the mountains." Of Course! The one in Switzerland! How could she have forgotten!

Three houses! (Plus some other ones that might not have been so nice)