Yeah, you're right, the methodology doesn't really inspire confidence in the results.

As an anecdote though, when I was vacationing there this summer all groceries, restaurants and similar felt incredibly cheap, and although rent on Manhattan was steep, I found a comparable apartment to my own in Williamsburg that had a slightly higher cost than what I am paying now. Maybe what I'm missing is health insurance? How much does it cost a normally fit 21 year old male for full coverage insurance?