Monocock, the Westminster you mention is quite expensive even by our standards. I seem to remember from the tariffs board the prices start at about £100 equivalent.
Sharpshot, I'm not sure about the French bank holidays although I suspect that our (UK) ones probably fill quite a few hotel rooms in L2k and around, especially in the Summer. For that matter I have been surprised just how difficult it can be to find hotels with vacancies when you need something on the day - ie when landing somewhere you were not sure you would be staying and therefore did not want to book in advance. Last year (August) I visited Le Touquet, Gerona & Minorca and had great difficulty finding anywhere at all to stay,
I'll take a tent in future on long trips "just in case,"
FujiF