Neighbor’s tree ripping up foundation (US-CA)

Wondering how best to deal with this. I own a commercial property with a parking lot and a small outbuilding that are being broken up by the roots of my neighbors ficus tree. Reading up on ficus, it looks like there is no real way to get it to stop ripping up the concrete, and would have to be removed. I’m doubting this neighbor would approve such a drastic action.

Are there any other remedies? If I salt the area the roots are intruding into, would it stop root intrusion? Anything else I can do?

What could I / should I ask of the neighbor?

Property is located in Southern California.

Thanks all