It is enough for general medical devices to apply for a utility model. 500 yuan, 75 yuan after reduction.
In Beijing, individuals with Beijing hukou apply for patent subsidies. After paying the fee, you can go through the subsidy formalities at the Beijing Intellectual Property Office and get the subsidy from the 75 yuan application fee, so it is equivalent to no cost. Other cities have similar subsidies, but they are all different. You can consult the local intellectual property office.
However, the annual fee \ registration fee and stamp duty must be paid when the patent is granted. Only the annual fee can be paid according to 15%, and the rest are full fees. After the patent is granted, an annual fee is paid every year to keep the patent valid, and the annual fee can be reduced or exempted up to three times.