You can but VPS is going to be easier because of the IP address.
You're partially correct on the IP's being different, you'll generally have a different LOCAL IP for each VM (they could be the same but generally they'll be different), you however won't have a different EXTERNAL IP. There's where the problem is because eBay only sees the external IP.
You can normally get around the external IP problem by resetting your router every time you switch VM's or between your host system AND verify the IP actually changed as short disconnects sometimes result in the same external IP being assigned to you by the ISP. Some ISP's aren't dynamic so you'll never get a new external IP.
The problem with doing all that? You could just setup new user accounts on the same computer and get the same result. Unless you have some specific reason to run multiple VM's at once (and then you'll need multiple proxys that aren't shared or it'll just end badly). If you need to run multiple accounts at once, even more reason to go the VPS route as it's far simpler.