Ebay Selling Question

[Omega Supreme]

Sorry if this is in the wrong section, please move this topic if such is the case.

Anyhow this is my current problem. I have sold an item to a user, the buyers address on file with both ebay & paypal contains no street address, without using the actual details this is basically what I have been given:

Joe Bloggs
..............
Cairns QLD 4011

The buyer has paid today via paypal, which I normally would send their item to the address they have on file with paypal, however due to the lack of details I was unable to do this, I contacted the buyer and informed the buyer that the address they have on file has no street name or number, to which I received a msg asking to send to a completely different name, suburb & postcode. This whole situation felt dodgy to me and also because of the fact ill never send to an unconfirmed address for transactions paid via paypal, I refunded the buyer and have cancelled the transaction(awaiting confirmation from buyer).

I have since received a msg threatening to leave me negative feedback, with a 100% positive record and to my understanding have done nothing wrong, besides stick to ebay & paypal policy, this is something I don't wish to occur.

My questions are:
1. Is there a way to stop this member from bidding on my auctions from now on ?
2. Will he even be able to leave me feedback seeing as I have refunded him ?
3. If the user does leave me negative feedback, will I be able to get it removed ?
4. If the user doesn't wish to proceed with the cancelled transaction, what would be my next step ?