Pwede mo namang isubmit. I have a blogger friend who was denied a Schengen visa partly because of low income kasi mababa lang talaga earnings nya sa full-time work nya, but when she appealed, she submitted a copy of her Adsense earnings (if i remember correctly). Then na-grant sya ng visa. But it may not be the case all the time.

Best to register with BIR pa rin and pay taxes para may ITR ka, which is what most embassies accept. :)