How do you fully stock in tiny tower

First you need some sort of store. Hire the maximum bitzens(3) to work there. Now start ordering products. You can only order 1 product at a time so order whatever has the most quantity first. Then second largest, then smallest(you might need to order some products twice). When you finish you should be rewarded with a tower buck(you don't get rewarded for the same store in one day, just repeat the next day).