I've been gainfully employed by Walgreen's since my second semester of undergrad, so I have worked at least a few hundred hours by the time I applied in the late fall of that year (we didn't need to list hours, though) and probably well over a thousand hours by the time I matriculated. It was ridiculously easy to find a job in a pharmacy in Omaha in 2002, even with two pharmacy schools in town. It still is, by the looks of it.