There is no property in the community, and the parking lot is built privately by the car seller at the door. Who should I find to solve it?

Who owns the public area of the community? Generally speaking, who cares who. Who rents the old house, who collects the rent and who manages it. You can ask the local real estate department. Then decide whether to take remedial measures such as litigation against the lazy behavior of managers in the implementation of management behavior, thus causing damage to you.