The cost of property installation monitoring and gate is not publicized. Can I refuse to pay?

First of all, you chose the wrong person. This should have nothing to do with the property.

According to the contents of the document in your photo, the installation monitoring and gate were actually put forward by the industry Committee, and the allocation of construction and installation costs was also decided by the industry Committee. According to the guiding rules of the owners' congress and the owners' committee, the owners' congress is convened by the industry committee to vote on matters related to the renovation of the community. If more than half of the owners agree to the scheme, it will be regarded as a valid resolution and binding on all owners. Even if objections are raised during voting, they must be implemented in accordance with the principle that the minority is subordinate to the majority. You can ask the industry Committee to show the resolution of the owners' meeting. If more than half of the owners really agree with this plan, you should also fulfill the obligation of payment. If there is no resolution of the owners' meeting, it belongs to the illegal operation of the industry Committee, and you have the right to refuse to pay the fee, and you can even propose to review the construction plan.