Check out thise threads:
[forumosa.com/taiwan/viewtopic.ph … =taiwanmex](Coming to Taiwan with a couple of questions (intro)
forumosa.com/taiwan/viewtopi … mex#411661
If you do a search using “hostels” you’ll come up with more. But any information more than a year old is unlikely to be helpful as the owners/managers of the hostel and its facilities may have changed significantly in the interim. Also, bear in mind that the time of year you go will influence what type of people you are likely to meet at the hostel.