\'right of first refusal\' means

"right of first refusal" means you accept their offer, but with a condition to leave the house on the market and continue to accept offers.

In case a new offer comes in, the 1st set of buyers has to perform withing a period of time. If they don't, then they give up their contract. You're free to sell to new buyers.

I suppose this is too late for you, but your agent should have known this and helped you make the best of the situation.
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