You can refuse any offer, period. Brokers might make up rules to prevent the seller from dithering (and increase chances of collecting commission) but that's different. You never have to take an offer. Contracts are mutual in general and particularly so in the sale of real property.

Do you have a citation for "seller must accept cash offer"?

Agreed-- sounds fishy to me, too. I'm not a lawyer. I'm not a licensed real estate sales agent in my locality either, but I did complete a course of training to that end. I never heard such a thing. If a seller were discriminating against a protected class in refusing such an offer that would be illegal. Holding-out for a better offer (whatever that memans) however, AFAIK, the seller's prerogative so long as they're not discriminating against a protected class.

In belgium a written counter-offer is binding. So, say a buyer makes an offer via email, the seller makes a counter-offer via email, the buyer accepts, then the seller is obligated to sell at that price to that buyer, even if a higher offer comes in from someone else. If they refuse to sell they can theoretically be forced to pay a fine, though in practice things usually don't escalate that far.

I can't find a citation so maybe I am mixing things up. If I do I'll post it.

In France, it doesn't even have to be a cash offer (although it mustn't have any contingencies beyond "buyer will get a loan"). This is mostly because most people in France don't have that kind of cash lying around, so if you only accept cash offers the rule applies to almost no one.

Of course, sellers prefer an asking price offer in cash, rather than with a loan that might be denied, so there's usually some (illegal) leeway if offers are received by mail. If you intend to make an offer contingent on a loan, make sure you print out the offer and bring it with you, and have the seller sign your copy. This lets you answer "There was another offer before you" with "That's not what it says on the paper you signed".

Interesting. I've heard people talk a lot about foreign all-cash buyers coming in and driving up prices. But if a non-contingent cash offer for asking price cannot be refused, then why would prices be driven up? Wouldn't these buyers just offer the asking price and save hundreds of thousands?

I'm curious to know more about how the non-discrimination laws apply here, since I know there definitely are laws, but if they are as blunt as described, then we'd expect to see more cash-offers-for-asking-price around here.

Prices can be driven up by someone going through and buying up houses reducing the supply, even at asking prices.

What if you receive another cash offer above ask? This seems to happen every day in hot markets (e.g. New York City).