Tough topic people.
I am not here to take sides on this one. No deposit was made, no written agreement with price, delivery, or deal was closed. This is one mans word against another. But a "scam"... I think that is strong word for verbal agreement that never actually closed.
Lets say you are negotiating a trade/deal... and in the span of a few days, a better offer is introduced by someone else? Should a seller (or buyer) be able to accept that offer if no trade is actually made? no deposit is made? No contract is documented? I say yes. That is freedom.
The issue here is one mans time & effort was allegedly wasted prior to a deal that fell apart. Does that make the other person a scammer?
On the other hand, a mans word should be worth something too... if he commits to something, he should do it. But in this case, no documentation is provided & signed by both parties. I would be upset if I had my heart set on a deal & it fell apart due to another motive, but that risk is always there.