For me it is and has always been an all consuming labour of love. I work on my business, in one form or another, 7 days a week - 365 days a year. Many would probably say that this is not healthy. The key is to appropriately balance the important things in life - family, health, friends & business.
Truth is . . . this sort of dedication is (and should be) no different than any other business one is building from the ground up. If you were opening a restaurant, it would be the same way. If you bought a franchise, it would be the same way. It is THE FAMILY BUSINESS and requires sacrifice and an overabundance of hours day in and day out to be successful.
The DJ profession is one of the toughest occupations in the world to succeed in. It therefore takes more dedication and occupies more time than most. From the moment I wake up until the time I go to sleep - the DJ business is on my mind. So too is my family.
So in answer to your question "How many hours each week" - the answer is EXCESSIVELY more than a regular job - a number CONSISTANT with other business owners building a business from the ground up and the OVERWHELMING MAJORITY of hours that are not spent with my family.
Well since I opened my new office, yes I got an office last week, I have been there from noon until 2am working not counting gig nights of course. I figure I was working at least 60 hours last week. Prior to that I figured 20 hours plus gigs and travel per week. If all goes to plan my increased effort and dedication will triple my business within the year, but I'll settle for double. Gotta aim high if you want to get anywhere these days.