Police are appealing for witnesses after burglars targeted five homes in Pound Hill.
The first incident happened when a 77-year-old went out with his wife for a few hours on Monday August 12.
When they returned at about 2.30pm they found their house in Worth Park Avenue had been searched and their possessions scattered.
The offenders took cash, gold earrings, gold chains and gold rings, including a diamond engagement ring.
It is believed the thieves may have got into the house by climbing onto a flat garage roof and forcing open a bathroom window.
The same thieves are also believed to have broken into a home in nearby Grattons Drive between 9.30am and 1.30pm that day.
A large quantity of jewellery and cash was taken before the victims returned.
Between 8.20am and 10.40am on Thursday August 15 a second home in Grattons Drive was broken into.
This time the thieves took a small quantity of Euros and Egyptian currency and two jewellery boxes.
On the same day a house in Pearson Road was entered and a DKNY ladies’ watch, a UK passport, a small amount of Euros and Egyptian jewellery were stolen.
The burglary happened after the owners went out, between 11.50am and 2.50pm.
Between 10.30am and 3.50pm a home in St Catherine’s Road was also broken into.
The burglars searched the property and escaped with a quantity of Euros, gold rings including wedding and engagement rings and other gold jewellery.
Officers are considering the possibility that the offenders used tools to open windows and doors from the outside.
Sussex Police has launched Operation Magpie to tackle burglary across the county.
Detective Constable Andrew Robinson said: “All of these homes were broken into in the middle of the day after their owners had gone out but when many other people were around.
“It is possible that the thieves watched the properties and deliberately waited for the owners to leave before they broke in.
“I am keen to speak to anyone who saw anyone acting suspiciously in the area or any suspicious vehicles.
“Please tell us anything you saw, no matter how insignificant it might seem to you.
“Someone must have seen something.”
Anyone with information should call 101 quoting serial 1013 of 12 August or the independent charity Crimestoppers anonymously on 0800 555111.