I don't know about Normandy, or exactly what you have in mind, but the (Dutch) agent who sold us our house recently (in Aveyron, Dept 12) works on a self-employed commission-only basis with a local estate agency called Selection Habitat. She reckons she is making a living (despite having to fund all costs herself), plus that the job has helped improve both her French and her knowledge of the local area. Good luck!