Depreciation Basis in High "Land Value" areas (i.e. SoCal)

[Courtney T.]

I’m converting my personal single-family home into a rental this year (Orange County, CA).

The County Assessor has the land valued at 87% of the total, which leaves a ridiculously low depreciable basis for the improvements ($120k). Given that the rebuild cost of a 1400 sqft / 4 bed would be 5x that, this doesn't reflect reality.

To get a more accurate depreciable basis, I have two data points:
* 2021 appraisal at time of purchase lists the dwelling at ~$350k.
* Current homeowners insurance dwelling coverage at ~$500k.

My questions for the group:

1. For those in high-land-value areas like OC, what are you using as your total depreciable tax basis?

2. Is it defensible to use the insurance dwelling replacement cost as the basis for a cost seg study? Appreciate any insight on how you’ve handled this with your CPAs.

3. Has anyone successfully petitioned Orange County to reassess the land vs. improvement ratio? Does this process carry a meaningful risk of the county reassessing the total property value upward, or is it generally contained to the allocation split?

Thank you everyone!