<human>: Can you condense the text into a few key points?

I REALLY hope I'm asking in the right place. It seems like you guys can help me here with advice.

Location: California (if it makes a difference).

A bit of backstory here. I'm in the process of getting accepted for an apartment and they asked us for a cosigner. This cosigner said they'd do it for us, filled out the application and whatnot. They got approved on everything (credit check ran) but then they asked for a proof of income.

Unfortunately, this person is self-employed. No pay stubs to produce. The apartment place said they would accept their tax form from the previous year. But this is a LOT of information for them to have about someone and doesn't seem that practical for proving insurance.

Do you know of another acceptable proof of income form they could produce without giving SO MUCH information to these people?
<bot>: Apartment place asked for proof of income, person is self employed and they asked for tax return. What can we produce instead?