Usually had 5-10 hours a month of DJing events (karaoke/dance) and I was in a band that played 3-5 shows a month, so that was about 10-20 hours a month (plus all of the time practicing, of course). The DJing was for a little extra money, but the band just so happened to be a lucky 2-in-1 experience where I got paid to do something I absolutely love doing. I also worked in the lab as a clean-up employee this past Fall, and that was around 2-4 hours a week.
I went to SMDEP after my freshman year, so I was unable to work. Last summer I received a research internship at the U.S. Meat Animal Research Center and will be going back again this summer and working until next year on a few papers. I have to work in the summer to support myself.
I have over 400 hours of non-clinical volunteering, 90 hours of clinical volunteering, have maintained a 3.91 GPA, and had a social life that met my expectations.
I worked much more than a few of my classmates, but I've also worked far less than the majority, I would say.