The price of white mushroom is very expensive, I always buy it from Food and Nutrition because it's much cheaper than outside, and the quality is not worse than that of supermarkets and malls.
The current price is 45 bucks for a 100g bag. These days, it's on sale for 38 yuan 100g per bag, so if you want to buy it, go check it out while it's on sale!
If you want to buy it too, go to Baidu and click "Food Nutrition"!