First off, eBay doesn't look at the first IP address established as the only IP address. Every time you login, your IP address is checked against other users. If eBay has a match to a suspended user, you will be suspended as well. So not being able to change your laptop IP address and using it anyway will only get you suspended.
And as long as you don't link your eBay and Paypal accounts, you can use any address you want with your Paypal account, if that's what you mean. | 
