Accidentally broke my roommate’s laptop

I live with two roommates, my best friend and her older brother. Her brother and I really dont get along. Today while I was home alone, I accidentally broke the guy’s laptop (Acer Chromebook R11). The screen is badly shattered and the back cover of the laptop’s body has cracked halfway down the middle. I feel awful and very guilty. I immediately told my best friend about the situation and also her brother. I offered to pay to repair/replace the laptop as needed. A brand new laptop would cost $400 plus tax. I also looked into replacing the screen, found one on Amazon for about $70. And I know that replacing a screen I usually easy enough to do yourself with directions from the internet. The crack in the back cover can simply be fixed with superglue since it doesn’t really effect the functionality of the laptop much. The dilemma is that he is a student and may need a laptop for school work etc. But I feel that since its holiday season and exams are mostly over, he can try to manage for a week or so while I order the parts. In the mean time, I dont mind lending him my laptop for use around the house. His sister thinks that I should buy a new one because she wants him to have it “at the earliest”. I do understand this but I have noticed he usually doesn’t even take the laptop to classes. Mainly uses it for assignments at home. Is it too greedy/unreasonable of me to want them to compromise a bit to help me save some money? I am a recent graduate, still on the lookout for a career job. Therefore I am trying my best to be cautious of unnecessary spending. Again, I do realize this is all my fault to begin with, but it really was an accident.