For your fast food restaurant, your suggestions are:

1. Record how many restaurants are around you with a notebook.

2. Observe every restaurant for a whole day, just watch it at the door, and use your mobile phone or notebook to record how many people went in for dinner all day today (don't be shy), remember. Watch every restaurant all day, don't be lazy or invite people, your own data is the most accurate.

3. Summarize how many customers each store receives for dinner in a day. If they are brands and yours is private, compare the data of the loudest brand store. If it can sell 1,111 fast foods every day, you can sell about 211-611 if you open near here. Convert it like this. If you are a brand store and others are private stores, if they can sell 611 copies, you can sell more than 1,211 copies.

4. If the survey concludes that there are not many people eating fast food around. You wouldn't have to open a shop here.