This is an insurance product which you take out when you are setting up a mortgage which covers you if you aren't able to complete on a house purchase
You take out this insurance at or before signing to a mortgage deal (like a higher lending charge). The insurance covers you against loss from solicitors fee, mortgage lending fees, survey fees, search fees etc if your planned house purchase falls through. Many house purchases fall through for various reasons and often they are not the fault of the planned purchaser, but the planned purchaser losses out. This product could be sold by mortgage lenders at the time of signing for a mortgage to protect any planned purchases against losses which are out of there control.
Problem this idea/invention addresses:
To recover cost that would have been lost when you plan to buy a house but the purchase falls through