Development of individual first-hand housing loan: At the beginning, the personal housing loan business of banks is in its infancy, banks have no practical experience, and consumers' overdraft consumption concept has not yet formed. In this case, dealing with retail business in a way similar to wholesale business is helpful to the rapid development of business. However, with the development of the whole real estate market and personal mortgage business, this mode of operation has become increasingly unsuitable for business development. The characteristics of personal mortgage marketing model make developers or intermediaries play an important role in business development and risk prevention. On the one hand, banks can realize the rapid development of personal mortgage business by marketing large developers, large real estate and intermediaries; On the other hand, it also makes the loan risk concentrated in developers and intermediaries. Once the property is rotten or false mortgage appears, the bank will face huge losses. For the end consumers of personal mortgage, they have no right to choose a bank. They can only choose banks that cooperate with developers or intermediaries to buy houses. If the bank handling daily business does not sign a cooperation agreement with the developer or intermediary, it will not be able to choose this bank to handle the loan, which may bring great inconvenience and waste of time, and it is also a huge loss of consumer welfare. The ultimate goal of developers or intermediaries is to achieve sales revenue. As one of the promotion methods, the fundamental goal is to achieve sales revenue in the shortest time. Banks should not only base their lending on the current stage, but more importantly, ensure the smooth recovery of future principal and interest. There is an inevitable contradiction between the two. In the increasingly fierce market competition, developers or intermediaries will inevitably force banks. If banks can't meet the requirements of developers or intermediaries, they may lose the source of personal mortgage business. Due to the pressure of their own tasks and profit targets, as well as the pressure of developers' sales, banks have lost the principle of independent approval and issued loans to some borrowers with potential risks. This weakening of the examination and approval mechanism will increase the risk of loans, and will also cause developers or intermediaries to defraud bank credit funds through fake mortgages and other forms.