I found this interesting
vacation rentals website. It allows the owners of vacation rentals to list their properties on the website. You as the traveller can then contact them directly to book your holiday rental. They cover a number of destinations worldwide including
Paris vacation rentals and
London vacation rentals.
I always think that a holiday rental is nicer than staying in a hotel, due to the fact you have a lot more privacy. Often it can work out a lot cheaper as well, so can be good for people travelling on a budget. For example I found a vacation rental in Oxford which starts from just £30 a night.