If there is tufeza from Los Angeles to Culiacán The ticket to Mazatlan I get 185 dollars from here from Los Angeles, there are only 3 hours difference, if it has to cost a little less, only if you go over 70 pounds they charge you in dollar the pound of luggage
There is no direct bus, you will have to get to Tijuana first, check the official TUFESA website (there are gringo and Mexican pages) luck
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