Duplexes that are sold individually and parceled differently aren't called duplexes. 

As far as backing out yes you can request your Escrow deposit back during the inspection period for any reason you deem fit, many individuals will say it is a free look however professionally that not the best description since it is not free, with any due diligence you invest in inspections and other professional services to answer as many unknowns as possible to remove as much risk as you can prior to purchase.

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I'd also suggest looking at some broad metrics regarding profitability (cap rate and cash on cash return) which will help you compare individual properties relative to other options.  

Like what Nabil mentioned, you may not able to recoup your losses if he has no assets or trail of any assets.If you signed the contract as an individual, you can get help from the city attorney when you file a lawsuit and present the case without attorney representation.I hope that helps, good luck.

You should hire a third party person that is approved by the seller like your title company or an attorney or any individual you both can trust. 

If to an individual, check for any probate proceedings.

I spoke to him on an individual level after the meeting about a 1031 exchange that a family member is looking to move from one property to a like kind property.

I am hoping to connect with more like-minded individuals in LA and hopefully be on my way to acquiring my first rental investment property by the end of this year!

Individual spaces are also categorized.