1, commercial loan. When the bank loan cannot be repaid, the court will auction the property to realize the repayment of the loan.
2. Private lending. In the loan relationship, the mortgage is repaid and the borrower's property is auctioned, and the proceeds are used for repayment.
3. Judicial confiscation. Confiscated property belongs to state-owned assets, and the proceeds from auction belong to the state treasury.
4. ownerless property. Unclaimed property can be auctioned, which rarely appears in reality.