How much to save for first purchase?

[Brad Koegel]

How much is a good amount of money to save up to make a downpayment on a multifamily? 

I would like to buy my first place soon but not sure what to set as a target number.  I know each area would have its own market, but what would be a reasonable amount to save for a duplex in a decent area?  

I'm currently a medical professional traveler, so I don't have a place to live permanently yet and am going to be moving to different cities/states over the next year at least 2-3 more times.  Any recommendations for markets to check out would be appreciated as well!