There’s a lot of this sh1t goes on, I sold used parts for 5 years. Bought them of ebay though, so I just used the claims process. I would avoid buying used stuff from the internet and use ebay. That way you can simply return the item for a refund loosing out only on postage.
The last 5 things I bought where so useless I sent them back, intense M3 with 10 cracks, a back wheel with a hub that didn’t rotate, a snapped spoke, 8 dings at least and a crack to the rim as well.
Hope you get this sorted out mate, I thought having to go through the claims process on feebay was a pain. having to go to court and sort out all the crap you must be dealing with, with any luck the bstard will have to pay all of the fee’s and costs as well as a hefty fine.
2000 distance selling regulations, cover this issue.
http://www.oft.gov.uk/about-the-oft/legal-powers/legal/distance-selling-regulations/
Good on you the thebikechain, you should be able to give some support and help get it sorted.
You might want to have expert reports written out on the condition of the frame including contact no’s and details on shop or company headed paper, might help your case.
Goodluck!