Changing the property management company without the owner's knowledge

Dear inquiry for you: changing the property company without the owner's knowledge from the perspective of legal contract: even in the early stage, the property company and the developer will sign a property service contract to limit the service time limit and breach of contract. Developers want to change the property service company, but also depends on the agreement of the property service contract, otherwise they will bear the liability for breach of contract; Second, from the perspective of owners' rights, a developer is the largest owner of a property if he has not sold half of the house, and has the right to hire and dismiss a property service company; If more than half of the houses have been sold, the right to dismiss and hire a property service company needs to be passed by more than half of the total number of owners and the total area.