<p>I think a prof needs to financially compensate any student in some way that works in their lab. One way is to work with the school and get a TA for the student. Another way is to fund them of off a grant. For masters students working in a prof’s lab, ~75% of the time they are paid hourly without tuition…occasionally they get full funding with a TA or full RA (tuition reimbursed). In my experience it is about 15% TA and 10% full RA for masters students working in labs. I would not work in a prof’s lab without some financial compensation. It is easy enough for a prof to pay hourly that you should not accept work in a lab otherwise. If you were to work without compensation, I think it would set the wrong tone for the relationship with you and that professor.</p>
<p>In Sciences like Bio or Physics you will need to do a research based masters if you ever want to do a PhD, else nobody will accept you into a PhD program. In engineering, it does not matter as much in the sense that the work experience you get in certain industry positions can be very valuable. My masters degree was just classes, but I had solid industry experience before my PhD. I kinda wish I would have done a research Masters in retrospect though. I think it would have helped at the beginning of my research in my PhD program.</p>