Assuming Citi is offering to waive the annual fee for the first year this appears to be a good deal. Go for it! ^
As for how tough they are on biz apps, not very IMHO, but the only way to know for sure is to apply as these things change.
Having an SSN only should not be a problem. I have gotten many biz cards using SSN, including from Citi.
Stating income from zero to $25K is a problem. Bank needs an exact figure. Take a closer look at your biz and see if you can make a fair projection for this year that includes some actual income.