Is it illegal to rent a shop privately?

First of all, as long as the lease contract between the property company and the hospital outpatient service is legal, then the owners' meeting has no right to interfere with its rental behavior.

Secondly, as the actual user of the property, the hospital has the obligation to abide by the owners' convention formulated by the owners' meeting. That is to say, if the hospital violates the owners' convention or infringes on the interests of the relevant owners, then the hospital is illegal. The hospital has the responsibility to compensate other owners for the losses caused by their illegal acts and rectify them immediately.

Finally, the community owners' assembly has no administrative power. If you want compensation, the first thing is to complain to the local property administrative department (property office of the real estate bureau) for arbitration, and the second thing is to bring a lawsuit to the local court.