[wahern]

California, at least, treats as a change in property ownership when a more than 50% interest in the legal owner (i.e. corporation, LLC, trust, etc) changes.

The rules don't completely address the problem. For example, I think some buildings are owned by consortiums so that nobody has more than a 50% stake. But that limits their ability to easily make management decisions; there's a cost to that structure. You definitely still see buildings sold out-right, so it's not like every building in California is owned by an LLC just to avoid reassessment.

[hedora]

The last time I checked, the 50% change in ownership had to be within one year in order to trigger the prop 13 revaluation (at least for commercial real estate). So, you transfer your corporate campus to an LLC, then sell 33% of it to a buyer this year, and agree to let them "run" the LLC, effective immediately. Next year, you sell another 33% of the LLC, and the year after, the last 33%.

What I don't understand is why this isn't standard practice for residential properties owned by individuals.

I assume you could use a combination of escrow accounts and collateralized loans to make the transaction mostly indistinguishable from wiring 100% of the money on the day of the sale. (I am not a lawyer or an accountant.)