Before I got involved in research, I had the perception that I would be expected to commit 15 hours a week or so. Most people in my lab, myself included, spent 3-9 hours per week, with more towards the 3 hour end.
One of my first posts here was very similar to this one. I was commuting, working to support myself, taking full time classes and lining up ECs. I was hoping my work experience would help adcoms overlook my lack of research and light ECs. My most important take away was that schools are inundated with applications that have everything: clinical experience, leadership, research, volunteering, working with diverse populations. Don't give your app a weak point if you don't have to.
I changed my mindset from "how can I get the minimum amount of ECs and apply by xyz date" to "how can I put together the best app?" In my experience, working against the clock will stress you out and may lead you to submit a half-baked app.