A lot of people that start eBay businesses get really excited about making millions and taking the auction site by storm.
It´s more likely, however, that your business will grow organically. You´ll chip away at daily tasks, improve your marketing skills, create better listings over time, and generally plant seeds at a pace that you can handle. Then you´ll wait out the growing seasons to reap better rewards and profits each time around. It will all snowball, and you´ll be making great dough in due time.
It´s just not going to happen all at once. Maybe it did for some, but those days are probably long gone by now. eBay is a thriving marketplace, but it´s not the gold rush town it once was, where people were flipping their baseball card collections for 150% profits.
I like to keep a quote from Teddy Roosevelt in mind when I´m building my own business and helping others add to their bottom lines:
"Do what you can, with what you have, where you are."
Great advice. If you show up every day and put in the necessary work to keep the wheels going, you´ll do fine. And you´ll find that what you have will become better every day (knowledge, resources, contacts, customers) and where you are will improve from week to week.