If you entrust an agency to represent a patent application, you need to pay an agency fee of about 2000 or 3000 yuan.
The key is to see if your patent is really valuable. Because the writing of patent application documents requires excellent patent knowledge. If the application documents are poorly written, it is very likely that the patent will not be authorized, or even if the patent is authorized, it will not be protected by the patent, because there are too many loopholes in the application documents, and others can easily use your patent without infringement by finding out your loopholes.
Therefore, if your patent is really valuable, it is suggested to find an agency, or take the time to write it yourself on the basis of mastering patent knowledge.