One area that you can upgrade multiple times are the cake toppers. The customers have a wide range of tastes. After playing a few levels, you will learn that certain customers tend to order the same type of cakes. The Granny customer tends to order two layer cakes and usually gets the Super Granny topper. When you first start a new month, you will be given a tip about is going on that month. Use this to your advantage. If you know there will be Cupids around, try to have the Snail Mail topper.