Insurance to cover buying/selling houses

[Katy May]

Hi. Does anyone know where I can get insurance to cover buying and selling houses? A friend said her solicitor offered insurance for selling her house (covering all costs if the sale fell through) and for buying her new house (again, covering costs etc). I can only find one site on the Internet which only covers for buying and is twice the price she paid, and my solicitor knows nothing about it,

Thank you.