Complaint Review: eBay

I recently listed a collection of photography equipment for sale on eBay. I clearly listed it "As-Is" and clearly stated that "I am not a photographer so I will list what I can, but the photos are a more accurate representation of what's for sale". I was emailed by the future buyer, who, as evidenced by this email, was aware he was buying the lot "as-is" and used that
fact to negotiate a lower price:
"Dear xxxxx,
Your price is reasonable even now.  But the problem is your items are not
inspected or tested.  So, I took the safe side to take care of any unexpected
none-working items... I'll place my $xxx.xx offer (including your Canon AE-1
with lens), Just for Today.  If it works, let me know.
Thanks anyway."
On top of that, the buyer is only disputing one camera out of the lot, which an
identical one was recently sold on eBay (#131109121424) for $29, which is only
1/7 of the total value. I even offered him a $30 refund for that camera but he
refused.
He opened a case and eBay somehow ruled in his favor. I have called multiple times but have since found a complaints page literally filled with other sellers with similar problems and NO help from eBay: community.ebay.com/t5/eBay-Cafe/Buyer-Complaints-eBay-Complaints-There-are-none/td-p/2922773