@Arn Cenedella, while the title of this thread is provocative, I honestly think it's misleading. Perhaps Cash Flow is King IF the goal of the investor is to build cash flow to replace W2 for whatever reason. In my case, Cash Flow was my #1 objective as I wanted to build up enough cash flow so I would have the choice to leave (or not) my W2 corporate gig.. Fortunately, after several years of buying cash flowing properties, I did get to point I could make that choice. I still kept working for a couple more years, but ultimately did retire and now spend my time managing my various real estate holdings.
I've had the honor of mentoring several others, several that I've met on BP, as they were getting started in their REI journey. I always tell them the #1 thing they need to define is "what are your goals".. Depending on your goals, your strategy will be different. To your point, those in their earlier years may decide capital appreciation is king. But, it all depends.