What is the ruling on dealing with the timeshare property system, which is based on an individual purchasing a property for specific days of the year, with his right to full disposal during these days, and the possibility of selling his share?

If the intent behind the "timeshare" system is that buyers share in the usufruct of a unit by rotation for a known period (such as a week), then this is closer to being a lease contract. Accordingly, the subscriber is permitted to utilize the benefit himself or through others during the agreed-upon period, and he may lease, lend, or deposit the property, provided that the conditions of the lease contract are observed.