For at least the last 3 years (the time my husband and I have been looking at this process), if there are no dependent children involved who have dependent children of their own, there is no minimum income requirement for the sponsor. You do need to provide tax information, but all they are really looking for on the sponsor's most recent tax assessment is that you are not on Welfare or Employment Insurance. There are people who sponsor with no income at all--if they are living with parents and going to school or something like that, and their parents are willing to support them--they simply explain this, and how they expect to support themselves and the applicant. Hell, if you won the lottery or got a big inheritance, I suppose that could even be a plausible explanation for how you would support the two of you on little or no income. Even with the sponsor having a low or no income, they surely must take into account that the applicant will likely be working once he has his PR and has landed after an outland application (or with an inland application for an applicant who also applies for an Open Work Permit, once he gets that within 4 months).
But really, all they are they are trying to ensure, is that if the applicant comes here and doesn't work, the government won't be having to pay for him. If that does happen (ie... your husband goes on Welfare or EI within the first 2 years that he's here, YOU have to pay all of it back).
Listen--I work at bloody Tim Horton's, and I'm sponsoring my husband. I'm not worried about them thinking I don't make enough money to support us both. Out of the last 2.5 years, my husband has been here with me (not working) for all but 6 months of it, and I haven't been on Welfare or EI... Money is tight, but we manage. And once he gets his OWP, we will have 2 household incomes and everything will be A-OK. That being said, when we sent in the application to extend his visitor status, I was paranoid they would think I didn't make enough to let him stay here with me for longer, so I sent copies of a year's worth of paystubs and made an incredibly detailed household budget and sent that along too, pretty much saying "See? He's been here already for 6 months a couple of times, and this is how we do it--it's worked before." The immigration officer probably looked at it and thought I was a nutcase lol, but I didn't want to take any chances and have to be separated again--it may have been overkill, but I'm sure it didn't hurt.
Anyway, I have this feeling you have the Canadian process rules mixed up with the American ones. Because we looked into both options, and in the States, there is a minimum income for the sponsor--I think it's about $22,000 a year right now, if the sponsor has no dependents and is only sponsoring one person. Plus in the States, I believe the applicant is not allowed to work for the first year or two of them being in the US--so that sort of explains why the sponsor would need a minimum income to support 2 people.
To summarize my ramblings: There is no minimum income requirement for the sponsor, if there are no dependents involved who have dependents of their own.
