How do you get a cash register on bakery story?

First there should be a design logo on the right bottom corner of the screen on bakery story then click it and there should be a bit where to buy tables then go right to the end of it using the arrows then it should be there. If you don't know where the table bit is then just go to the very left one on the menu. You should get it when you start the game but if you don't then don't worry. It is 80,000 coins so you might need to store some cash for a long time.