I might be wrong, but I don't think that means that it was sold for 57k, only that it was the asking price.

That's true but the article does mention how most of the things that impact price went in patio11's favor. One can reasonably infer that if the seller feels everything went in his favor at the end of the process that he wasn't bullied too far off of his asking price.

He does also mention how one seller tried to demand a 40% discount at close, and that the broker had a better deal waiting in the wings. So we can have a pretty high degree of certainty that the sale price was between $28,500 and $57,000, likely closer to $57k.