Well you will need eBay and places like ecrater, but mostly to drive even more business to your store.
There are alot of free places like
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And the newest one which has some very good items.
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But still, you are going to need an account probably at bidz.com and Link hidden: Login to view
Those will give you better profit margins. And the easiest way is to just buy in bulk, have every item sold at a different price and drive a huge load of traffic to your website.
A tip...DON'T pay for advertising..most everything out there that is worthwhile is free. And DON'T pay eBay's monstrous fees.
You can still use eBay and even uBid without paying monstrous reseller fees, just use only the value pack and list the item. Typical products you sell this way cost as low as $3.00 to list.
I've even listed for about $1.65 this way and still sell the items....why use the extras, if you can get everyone to come for free and buy anyway?
Yes that is the key to online success....take it from me, once you see the ways to market and win at your website for free you never go back. I have made sales orders right direct off my website, they go to the auction listings from there. And with nearly 2000 hits its easy to see why....and just imagine you could have a FREE store on ecrater, and another, and STILL drive everybody to your place.
Then fill all the orders.