Bingo.
The fact that the advertised price changed very shortly after you saw it and ordered makes me inclined to agree that it was just a mistake on the advertisers part.
Seller beware sometimes does happen
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About 45 years ago I answered an ad for a batch of canoes for sale, part of a half dozen 3 and 4 year old boats that a rental company was getting rid of in line for replacements in their fleet. I didn't have much money at all, but the asking price of $200 each was attractive, so I went over to look. 5 where 17' fiberglass lake boats, nice enough models, probably $500 boats new, aluminum gunnels, thwarts, and seat frames, plastic seats ...but one was a 16' Royalex whitewater model, oak gunnels, thwarts, and seat frames, snowshoe style leather woven seats...new cost would have been closer to $1500 even way back then.
The rental company owner showed them to me, all 6, on his beach...I clarified, "$200 for any of them?"..."Yup", says he. I replied, "I'll take that yellow one, then". $200 cash exchanged, I loaded the boat on my station wagon rack and headed back to my then place of employment and residence...an exclusive residential boy's camp in central New Hampshire, on Lake Winnipesaukee.
Next day, I get called up to the camp office to answer a phone call. It was the canoe rental co. owner. He tells me he made a mistake, that boat was not for sale at that price, he wanted it back, unless I wanted it for $500 more.
You might guess what my answer was
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That canoe resides in my shed today. That was a good buy
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