The bank brought forward the settlement date but did not tell her. As a result, she arranged for movers to get her belongings, not knowing the new owners had moved in.
The new owners wouldn't give the movers access to the home, and refused later requests to have her belongings returned.
"In addition to usual household chattels, Mrs L had lost personal pictures, videos and family mementos, as well as her children's toys and furniture," the case note states.
She went to the police for help but was told it was a civil and not criminal matter.
The Ombudsman found that the bank - which was not named in the case note - should have taken steps to notify the woman of the change in settlement date.
Despite that, it did not consider the bank liable for all of the loss suffered by the woman - noting it was unusual for new owners to be so unhelpful.
"We did find that the bank had contributed to her loss ... we also observed that when she first raised this issue with the bank it did not assist by contacting the purchasers or their solicitors to try to persuade them to co-operate."
It was recommended that the bank pay $8000 for the personal inconvenience suffered by the woman, and a $5000 contribution towards her legal costs.
A further $500 was awarded because of poor communication about a related matter about car debt repayment.
The woman was disappointed with the compensation, but accepted it.
The Banking Ombudsman scheme is a free and independent service which helps people resolve problems they have with participating banks.