What does it mean to buy back government property for free?

When the government buys back real estate, it chooses paid or unpaid methods according to the situation. Paid repurchase means that the government buys back houses from the owners of houses at a certain price, and then sells them to other buyers or carries out other development and construction at a certain price. Free repurchase means that the government does not pay any fees when buying back houses, but gives certain compensation to the owners of houses according to the actual situation of houses.