CSS profile for international student

Hi guys,
I am crazily confused about the CSS so please forgive me if there are silly mistakes I might make.
So my family owes a small business (more like self-employed cos we dont have employess,) so we need to submit the tax return?
About the asset, if we can not remember the price of our house but its price is pretty high now so how can we fill in this part in CSS?

About the Parent expense part, the number we put in is just estimated or we will need some papers to submit to prove that? I am really confused

Thank you for reading this