The British man shot dead in the French Alps hid important documents inside his own home before leaving for his holiday.
Saad al Hilli, 50, was shot with his wife Iqbal and an elderly relative when their car was targeted on a remote mountain road.
A close family friend in the UK has spoken to Sky News and said that two months before their holiday Mr al Hilli suffered from heart palpitations and spent a night in hospital.
The friend, who didn't want to be identified, also revealed that Mr al Hilli had been very concerned about some documents the day before he left for the caravan trip to France.
Other neighbours in Claygate, Surrey, have confirmed that he had expressed concerns about security at the family home shortly before they left.
The family friend who has known Mr al Hilli for many years was also asked to "keep an eye on the house" and even offered to take the documents for safekeeping.
Mr al Hilli told the friend: "No, don't worry I've hidden them somewhere inside."
Police searches are continuing at the family home and French detectives have based themselves at Woking police station while they continue their work to see if there is any reason why the family could have been targeted.
The elaborate theories that have been put forward have baffled many friends and relatives of the al Hilli family.
"He was just a nice decent guy," the family friend added.