I didn't say it was underhand. I said I assume the seller would be happy to negoatiate a new price.
I mean, if you found out someone had misunderstood and thought something was included when it wasn't, sure you might be a bit disappointed but once you knew that they'd based their offer on faulty information you'd not expect them to still pay the same price would you? I mean, that would be entitled and underhand!
I don't especially sit on either the buyers' side or the sellers' side, but I do care about fair and efficient markets and I'm pretty aghast at some of the comments being made.
In the case of house sales, other than unknown nasties in the searches or surveys, the seller has all the information going in and the buyer has none. That gives the seller a lot of uneven power in the initial agreement.
What I aim to do is to remind sellers that it is entirely reasonable for buyers to need to adjust their offer as they gather more information. Indeed it's the reason we don't set a binding price until exchange.
So whether a seller thinks that buyers "should" assume something will or will not be included when they offer is not really relevent.
The reality is that if a buyer has offered based on faulty information they have both a legal and a moral right to conclude their original offer is now overpriced and reopen negotiations.
The seller likewise has every right to refuse. And if the buyer and seller cannot come to an agreement it goes back on the market.
What the seller cannot do is force the buyer to buy at the original offer simply because the seller thinks the buyer "should" have known something that the seller did not in fact bother to tell them.
(Though I have to admit I do wonder whether all the "it's just bricks and mortar" posters would expect a lovely finished property to sell for the same price as the doer-upper next door.)