Living in France

We have a flat in Tarbes but pay around 300 euro a month charges, tax habitation an functionere (forgive spelling) and then the syndic. It seems excessive but maybe not. But when I speak with friends etc, they say France is much cheaper to live in than London. How do they come to this conclusion, am I missing something? Can I ask on average how much it costs per month to live after you have paid property tax. Do others agree that France is cheaper than London to live?