If I can give you my personal experience : I began my computer degree with a Dell latitude 7240 that I bought on ebay for 250usd. The best computer I ever used I think (except for the screen and is low resolution).
Later on I bought a Surface Pro, good laptop, but expensive and battery life is lower than the Dell, but the screen is better... You need to take care of it, unlike the Dell.
My thought, go second hand, Lenovo thinkPad or Dell Latitude 7000 or 5000 series. Easy to find on eBay and very very reliable.