I spent ages trawling the internet for holiday homes to rent on Ile de Ré and in La Rochelle. www.abritel.fr seemed to be the best, and most comprehensive, website. We ended up with a wonderful 2 bedroom stone house on a narrow, quiet street a stone's throw from the main square and the main supermarket in Ars-en-Re. Rented from a certain Pascal in Paris. They have an English version and you contact the owners directly.
The site caters to all of France, by the way.
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