claire - marseillan

I have owned a property in France for the last 4 years and love the region we live in. For the last 4 years we have had our eye on a derelict house and have been watching to see if the property would be put up for sale. Currently it is still unloved and we would love to purchase it and completely renovate it. How do I find out who owns the property and if they would want to sell it. Are there any pitfalls in doing this??? and would there be any obstacles I may encounter (apart from people not wanting to sell it) that may mean that the owners can't sell the house?? Thanks in advance Claire