buy a new second hand laptop for university

Hi, my name is Billy and I am in need of a new laptop for my course. My current one is nearly reaching 10 years of use and it is starting to break down with the charging port becoming very hot during use and the laptop being very slow. I'm only looking for a used laptop, so I don't want to collect too much money. I am 19 years old and is currently taking a Bachelor of Architecture at Monash University and having a laptop is essential for modeling work done on campus. Unfortunately, due to financial constraints, I am unable to afford a suitable laptop that meets the needs of the course. Being an international student comes with additional expenses such as tuition, accommodation, and daily living costs, making it difficult to save up for a laptop on my own.