Though a significant upfront investment, in the long run the cost is fairly immaterial. What more concerns me is leaving SoCal for 2 years only to come back to it later. It does not seem to make a lot of sense; at the same time it is going to be somewhat boring to hang around LA. If I were in your shoes, I would be on the fence too.
I think it comes down to personality - if you are adventurous (a gambling person) - then Columbia has your name on it. It has more excitement, greater risk, and a greater return potential. You have a chance to start from scratch and redefine yourself.
If you want to play safe - then UCLA is a perfect choice - it is free tuition, you stay in town and leverage your friends/family/professional network and keep the costs down. This is esp helpful if you have a relationship you don't want to end.
Both schools have enough fire power to get you to where you want to be. You won't be guaranteed the best spots as you will be competing with a lot of other grads for the prestigious MBB slots but you will get something.
P.S. I was poor at my time of matriculation so I would have picked UCLA as the only realistic option. Borrowing 100K or 50K more was unfathomable for me. Had I had the money, I would have gone to CBS - I wanted adventure.
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