To do business, you should first investigate the market where you are located, the location, technology, time and cost you want to operate, whether you have a good location, whether you can go in, how much money you get, whether the money you get back is in direct proportion, whether it suits the tastes of local people, what units are in charge of it, how much is the daily cost, how long it takes to prepare materials, how long it takes to clean them, and how much is the waste. Of course, it is best to give back at most. Finally, what is your development goal, how long you want to work, and how far you want to develop. There are also problems that you can think of yourself. Think clearly before you start!