Financial requirements for the sponsor in family class

Hello,
My boyfriend is canadian and he would like to sponsor me via Family Class and as my common-law partner. We would meet the common-law requirements because we have actually lived together for a year and are a couple since 4 years (with a lot of proofs needed available).
However, I am still clueless about the financial requirements he has to meet and what kind of statement or proof of business activities he has to provide. He is self-employed in his own unincorporated business. I have read a few times that “A sponsor must demonstrate a level of income that meets the minimum necessary income.... The Sponsor is freed from this requirement if: The individual requiring sponsorship is the common-law partner of the canadian sponsor”
1)Does this mean that he does not have to provide any financial information? The question regarding the “Net personal income of the past 12 month” can be skipped in the form IMM 5481?
2)Does he still have to provide the option C printout? Does this not show his income from the last taxation year? What is if it shows less than the $20,778 (minimum necessary income for 1 person)?
3)How would the evidence of self-employment income have to look like?
4)Should the question if he is “currently employed” be answered with YES because he is self-employed?

It would be great if you would help out with some information. Thank you very much, Nicole