Which type of dump truck should I buy for California?

Make sure it's electric..
Then be prepaid to have to shut down during a heatwave because you can't recharge the batteries due to the weak power gird

 

Super 10 or maybe a super tag. 2016 or newer just to be safe from all the regulations with DEF and EGR issues. Do yourself a favor and buy a truck that was made to be a dump truck. I’ve seen so many people have OTR trucks outfitted into dump trucks and realize that the engine/suspension/transmission are all under powered or too weak.
Stay away from buying a transfer dump unless you have the work/connect for it before purchasing. Most guys won’t rent one hourly unless necessary. Most move loads per ton. It’s more so for convenience for rock/landscape business.

 

If your talking about double belly dumps, 2 axle truck with single axle trailer/pup combination. I feel you’ll be limited to the type of work those trucks do. Roadbase and jobsite aggregate delivery is mostly what I’ve seen them do.
I’m not sure how well you’re vested into the cali dump/dirt work market yet but I do know a lot of it is thru brokers. Have you gotten rates yet? Do you feel you’ll be able to make a living jumping into dirt work? I run with a brokerage out of Vegas, they have work with Sully Miller and Security Paving in California but it wasn’t enough to convince me of sending a truck there. Pricing insurance cost to run in California and fuel versus price per hour didn’t balance well for me.

 

Captain Obvious says-

How about talking to the brokers in your area that you will be working for and asking them which setup they have the most demand for?

 

Shouldn't you know who you're going to work for before you buy a truck?

Seems to me like it would greatly increase your chances of success