I doubt most buyers would have any idea what a "fit sample" is.
If the garment has been tailored and re-tailored from its original manufacture, I would think it would be considered used.
I have noticed that sellers of "runway used" garments seem to mention this as a plus. But I would assume that these have had a little extra work done to fit them to the models more precisely.
Sellers are not even required to give measurements although any seller who doesn't is asking for Not As Described returns.
If you are not happy with the item, ask the seller for a refund on return. She cannot in practical terms refuse this, even if her listings say "No Returns". Be polite and explain your problem precisely. And politely.
She may if you are really polite and charming, offer to pay return shipping in whole or in part. Use a Confirmed Delivery service.
She is not required to pay for return shipping. Mention it, but don't count on it.
