I've noticed several ads of people looking to buy old cars in any shape, any year and mileage, like this one: http://www.anibis.ch/fr/automobiles-cherche-voiture--72/achat-cash-voituresbus4x4-toute-marque--8174232.aspx?loc=gen%C3%A8ve&sdc=30&fcid=72

My question is: anyone of you had experience with this?

I'm selling and old car and wanted to know whether these ads might be a good deal or there might be something one should be careful about.

Thanks in advance.