I occasionally sell things on Ebay, and even though it's not not a "real business", it generates a very very very small income (in hundreds of dollars, not thousands). Whenever I apply for business card, I truthfully state what it is, and so far - I had always been approved. Perhaps it helped that my main income (from employment, not from Ebay "business") is relatively high and my credit score is in 800s. What doesn't help is that I have a lot (12+) hard pulls in the past year. That's why I am somewhat hesitant to apply again so soon...