A prospective buyer is thought to have stolen jewellery worth £7,000 after viewing a house that was for sale.
The woman had visited the house on Coggeshall Road, Braintree, twice on April 17.
After she had gone, the owner noticed jewellery and watches were missing from her bedroom.
Investigating officer PC Sarah Robinson said: "The woman viewing the property gave a false name and address. She was reluctant to provide the estate agents with her details and may have given them a false telephone number.”
The suspect is described as white, in her 30s and had dark brown hair worn in a ponytail.
Police advised anyone selling their homes to always accompany potential buyers throughout a viewing, follow them into each room and never allow them or their partners to wander off on their own to other parts of the property.
Call PC Robinson on Essex Police 101 or contact Crimestoppers anonymously on 0800 555 111 with any information.