It's a small but growing problem in the property market - here's how to protect yourself.

Sarah was excitedly packing up to move out of the terraced house her family had outgrown to a four-bedroom home in the countryside. But the day before exchanging contracts the buyers of her house dropped their agreed offer by £15,000. "It was awful, your heart just drops to your stomach," says Sarah, not her real name. She had fallen victim to gazundering, a rare but growing problem in the property market in England and Wales, according to the Conveyancing Association, external. It is calling for government reforms aimed at tackling this and other house buying and selling issues to be brought in "without delay" instead of 2029 as planned. They were selling the three-bedroom terrace they'd renovated and buying her parents' four-bedroom detached house in the countryside. But the day before contracts were exchanged Sarah received a phone call from her "befuddled" estate agent saying he had some bad news. Their buyers said they'd done some more research about the area and would now offer £15,000 less than the price they'd agreed. "I can't even begin to go through the financial consequences [if we lost the sale]," she says.