Timeshares purchased on the primary market, e.g. from the developer, include the cost of building plus the cost to sell plus the profit margin, just as with any other product. Combine that with the fact that there are millions of timeshare units for sale on the secondary market and the fact that many developers are restricting the rights and benefits to secondary market purchasers, the value of most timeshare is considerably lower than most owners realize. It is simply supply vs. demand vs. benefit.