When renting a storefront, first check before signing whether the unit can be used for your kind of shop: converting a residence into a shop needs the consent of all the owners in the same building, and a new restaurant that produces cooking fumes can't open in a residential building

In plain words

To convert a residence into a shop, all the other owners in the same building must agree, and a single objection is enough to block it. If a neighbor sues you to restore the original condition and pay compensation, the court will support them. New restaurants that produce cooking fumes are not allowed in residential buildings or in mixed commercial-residential buildings without a dedicated flue; if you are found, you are told to fix it first. If you don't, the shop is closed and you are fined 10,000 to 100,000 (1万到10万) CNY, and your renovation money and deposit may be lost that way.