Each apartment has its own clear check-in time. If you arrive in the United States after the official check-in time of the apartment, of course you can check in directly after going through the check-in procedures. However, if you arrive before the official check-in time stipulated by the apartment, you should: 1) Communicate with the apartment in time when applying for the apartment to see if there is the possibility of early check-in and tell the apartment your ideal check-in time; 2) If the apartment cannot provide early check-in, you need to find temporary accommodation by yourself, such as hotels, daily rental houses, or ask for help from early students.