It's not uncommon for them to reject any and all initial and subsequent offers. A popular tactic is to put in a low list price to initiate a biddiong war, don't get caught in that trap either.
In a multiple offer situation they will go back to everyone that has submitted an offer and ask them to resubmit their highest and best. However, they do not have to accept any of the offers but more than likely they will take the best. Please note that it does not always have to be the one for the most money. Cash deals are very viable because they can close quickly.
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RE/MAX Around Atlanta