There are more gains, but these are the preeminent ones. For instance, a family who has purchased a plot of land in New York for the purpose of moving nearer to large city in the future. Unfortunately, the family experiences heavy financial crisis because two of their children have to pay high University Fees. Thanks to this special source of finance, the short-term problem can easily be solved. The family can reduce the cash outflow, by either negotiating with the lender (to perform a lump sum payment the following month), or if the collateral value of the land has increased, the same land company can find a buyer so that you can sell your land. If the land has appreciated sufficiently you will end up with a profit.
This is a simple example too show you why borrowing money from a company which sells land is better than questing for money from banks. First, it is difficult to obtain if your financial record is poor or if you have not had a stable income since the last 2 years. The bank will definitely under-valuate the price "collateral" of the land. The loan that you will obtain might be insufficient to purchase the plot of land.