A seller liable for eviction must return the full price to the buyer even if, at the time of the eviction, the value of the thing has been diminished due to any cause including the buyer's neglect.
Nevertheless, if the buyer has benefited from a diminution in value caused by his own act, the amount of his benefit must be deducted from the total owed to him by the seller because of the eviction.
La. C.C. § 2507