For those who don't know the system of this game:
1. If you sell products, the price will go down
2. So I suggest you don't sell all the products, and just keep it (but first you need to upgrade your storage, prods. per day, etc.)
3. The longer you wait, the higher the price will be, then sell it
+) Cheese is the best option I think, so keep storing cheese
+) Eggs are not good option cuz wolf girl comes every monday and takes half of eggs you have