Very little to add here!
I just wanted to say that there are times in life when it is good to go the extra mile, and there are times in life when you just have to focus on the basics. I am going to guess that, since you are living in a hostel, you are probably not in the best personal or financial situation and have other priorities.
So, it's great if everything around you can be tahir. It's not good to live around najasa like alcohol. I knew a woman once who was extremely proud of the fact that her entire house, including the toilet, was always tahir. (To which my other friend said, "Is she planning to eat from the toilet??")
On the other hand, as Seyed Ali Shobayri mentioned, the main sources of concern are: (a) eating and drinking (so, for instance, washing shared cups before using), and (b) purity regarding prayer. Everything else is excellent but may not be your priority right now.
I hope you are able to find a living situation where you have more control over your environment in the future!