Use the following trick if you do not have a lot of money and want to buy goods or an object to gain more skill to get a promotion. Buy the particular goods that will help you for a promotion (for example, an exercise machine, or book shelf) and study the knowledge (for example, cleaning). When you get a skill point, delete the item that you bought (sell it before 24 hours have elapsed). You will a get full refund back from that object. If you sell after 24 hours, you will get less money. By doing this, you will gain your skill without losing your money.
