Can the fees charged by the old property be refunded after the handover of the old and new properties?

If it is legal, you can bring a lawsuit to the people's court for recovery. As long as it meets the conditions for prosecution, it is legal. The prosecution must meet the following conditions: (1) the plaintiff is a citizen, legal person and other organization that has a direct interest in the case; (2) Having a clear defendant; (3) Having specific requests, facts and reasons; (4) It falls within the scope of civil litigation accepted by the people's court and is under the jurisdiction of the sued people's court.

People's Republic of China (PRC) Civil Procedure Law

Article 119 A prosecution must meet the following conditions: (1) The plaintiff is a citizen, legal person and other organization that has a direct interest in the case; (2) Having a clear defendant; (3) Having specific requests, facts and reasons; (4) It falls within the scope of civil litigation accepted by the people's court and is under the jurisdiction of the sued people's court.

(1) The name, sex, age, nationality, occupation, work unit, domicile and contact information of the plaintiff, the name and domicile of the legal person or other organization, and the name, position and contact information of the legal representative or principal responsible person; (2) Information such as the name, gender, work unit and domicile of the defendant, and information such as the name and domicile of the legal person or other organization; (3) the request and the facts and reasons on which it is based; (4) Evidence and its sources, names and residences of witnesses.