Government procurement does not always need to go through public bidding procedures or be handed over to centralized procurement centers for procurement. According to the relevant provisions of the Government Procurement Law, as long as the purchaser has the professional knowledge and purchasing ability of the purchased product, and the product is not in the centralized procurement catalogue, the purchaser can organize the procurement by himself.
The specific rebate and price depend on your communication with suppliers. Although it is not advocated in principle, it is an open secret.