I agree that London is way too expensive as a place to stay for the whole time. My advice is to seek out a rental for the whole period in a location that is more central on the Continent. Go to one of the many house/aparment rental sites and check them out. You can specify exactly what you want and the agents will find you something. We have done this with RentVillas.com. Found a spectacular farm house in Tuscany and planted there for a few weeks. There are plenty of city apartments available and a smaller city would be ideal for such a long stay.

Lucy