So when a house is listed for sale for an asking price, does that mean the seller is obligated to sell for only that amount? The seller came up with that price tag in the first place.

> I feel like a key difference here is that the owner was initially willing to sell for $50k.

He said it as a clear joke. Here's a ridiculously huge number for a novelty, a bauble - now go away.

The owner never stated a willingness to sell, just a price.

If you come up to me while I riding my bike and says "I'll give you 25 dollars for that" and I respond "it's price is 500 dollars firm", that doesn't mean you can then give me 500 dollars and take my bike or sue me for refusing. That is ridiculous.

Even if I did have an intention of selling the bike at that price, I am in the middle of using it and can easily accept or reject attempts to buy it at a time that is inconvenient for me. Similarly, it is also my right to choose who buys my bike at that price. If it has strong emotional value I may refuse to sell it to someone who I don't think will treat it well.