Faasid sales

To sell a slave on the condition that the buyer frees it or that the seller uses it for a month after the sale. To sell a house where the seller will stay therein for a stipulated period of time (after the sale). To sell something on condition that the seller will only hand it over at the beginning of the month (after the sale) or that the buyer must give the seller a loan after the sale, or that the buyer give the seller a gift. All these types of conditions render a sale Faasid (Kitaabul Buyoo).