Sellers can no longer give negative feedback on buyers. Your contract with the seller does not include collection within 48 hours - presumably simply buyer collects. You cannot be unreasonable and say you will collect in 10 weeks time, but equally he cannot be unreasonable either, and his demand and "threat" is at this stage unreasonable. If you have not yet paid your easiest option is to pull out and at once (or even before you tell the seller) advise eBay you are doing so because the seller may try to report you. Warning: try to do all your communications through the eBay messaging system because then eBay can look up the exchange in their system and see what you have said. The eBay system is sometimes a bit fiddly, slow and erratic but it is worth using it - remember to tick for a copy to your e-mail address. In my experience, eBay are pretty good at protecting buyers who are in the right. Do not accept outside storage, even if he accepts it is at his risk. Good luck.