The disadvantage is that class is inconvenient. I may live far from my class and have to get up early in the morning. Getting up early in winter is also difficult for poor households to get up early every day.
There's a little financial pressure. If you have to pay part of the living expenses and rent, the rest may not be enough to eat. However, if you live outside and have free time, you can find a part-time job to support yourself. Counting your income and expenses every day can not only exercise your financial management ability, but also develop good living habits.
Need to consider security issues. It's not safer outside than in school, so always keep in mind the safety problem.
Whether to rent a house off campus depends on your own situation.