I believe there are too many variables in your question, and in the answer, to give you a good answer to your question here. What are your goals? Who will live in the unit? Is it a rental? Are you looking for cash flow? What part of each neighborhood are you considering? Beverly Hills is unlike West Hollywood, which are both unlike Century City, and downtown is a whole different animal. Real estate is neighborhood specific.
Don't be lured buy the new vs. old distinction; in 7 years, what was new when you bought it will be resale, and in downtown, more new will most likely be available at that time. Also, building quality of an old BH duplex will stand up against a downtown loft any day.
Consider all of these variables (and more I have not listed) before making a buying decision, especially when buying for investment.
The Bremner Group at Coldwell Banker
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