I sold a property last year that required the owner to get a certificate of nonconformity to be a legal two family.

Regarding number one, while it may or may not be legally necessary (not sure), I think it's a good idea to have a separate account for each entity.

I even have a friend who received an unfounded complaint from a neighbor (the neighbor was just against STRs, no events/parties that occurred), and now their property is temporarily banned/under review, regardless of them abiding by all rules.

Taking legal action against another party necessarily involves questions of law and can result detrimental legal impacts on him if he files a lawsuit without proper grounds to do so, or where the opposing party may have counter-claims against him.

We do get some showing complaints, but 98% of the times, kids are understanding and are fine with it.

Exhibit A -a page with the legal description of the property  3.

It makes ADUs under 900 sq. ft. in SF zones legal BY RIGHT, statewide, starting in February.

If the issue continues, consider offering a formal payment plan or seeking legal advice.

For instance my 90 lot subdivision at one point I had 90 legal descriptions and parcels on one master deed.. as I sold them off we just deeded them out separately.. its super common especially in older platted cities were lots might have been small like 25 X 100 and someone bought 3 of them and then built one home on all three.. some places they force merge them others you can go back and recreate the Old lots of record.. there is millions upon millions made by those that know how to find shadow plats and bring to life underlying parcels.

The next question is whether the property has the zoning to legally operate as a 2 or 3 unit building.