Subdividing large lot in Orange County, CA - how hard is it?

[Ali Mo]

Hi all, 

If this isn't the right subforum for this, please let me know where to move my question to. 

Summary:
How hard is it to get a lot subdivided in Orange County?  Any rough ideas on how long it would take for it to get approved?

Details:
We're interested in a property in Orange County for our primary residence.  But we can only reasonably afford it if we can subdivide the lot and sell the back half of the lot.  If you look at the image below, you'll see that the front half of the property has a home and landscaped back yard, and there's essentially a wall separating the developed front half of the property from the undeveloped back half.  Lot size is ~1 acre.  In the top-right corner, there's a gate that can open up into a major street, so there is street access for the back half of the lot. 

Does anyone have experience with subdividing in California/OC?  How challenging/time-consuming would it be?  Our plan is to by the whole property, subdivide it into 2 lots, and then sell the (undeveloped) back lot to lower our net cost on the (developed) front lot. We don't have the money to develop the land, otherwise, I'd consider building some ADUs and renting them out to university students. 

Thanks!