Mystery surrounds the disappearance of Bert Scheepers, a well-known businessman, farmer and car collector in Knysna, a week ago.
Egbertus Johannes Scheepers, 65, was last seen at his home in Thesen Island last Thursday.
His family is desperately trying to track him down and on Thursday confirmed that they have hired private investigator Mike Bolhuis and his team to follow up all leads.
"We will do a national search... I have been given the complete case and have already given it to my unit," Bolhuis said.
Scheepers, who owns House of Classic and Sports Cars in Knysna, left for work around 08:00 that day, according to Western Cape police.
His partner reported him missing at the local police station on Friday, said Captain Malcolm Pojie.
His daughter Lisa said on Thursday that he left his personal belongings and vehicle at home.
CCTV footage could apparently not show that he had left the island.
Police released information on his disappearance on Monday, which is when Lisa, who lives in Johannesburg and her mother, who lives in Nelspruit, found out he was missing.
"This was shocking and emotional news," Lisa told Bolhuis in a letter.
She eventually managed to speak to different people with information, including her father's partner.
Lisa and her mother flew to George and drove to Knysna on Tuesday.
"No suicide note was found, he left his wallet and cellphone and new laptop at the house," she said.
According to a circular issued to Thesen Island homeowners, search parties have combed the area as a whole. Sniffer dogs, a drone and divers were also used to no avail.
The search is also focusing on other areas and properties he visited.
"He travels a lot to Cape Town, the farm, the house in Plett and to Johannesburg for his advertising business in Strijdom Park, Millenium Advertising. He would stay at the City Lodge, near Sandton Clinic," said Lisa.
Scheepers is around 1.9m tall and weighs about 90kg. He has blue eyes and grey hair, which is sometimes coloured.
He was dressed in dark trousers and a light blue, long-sleeved top at the time of his disappearance.
His family have described him as a private, quiet and reserved man.
Bolhuis hoped that someone would come forward with more information.
He said that he had dealt with many missing person cases and there were many reasons for those disappearances. These included memory loss, health problems, taking one's own life, possible crime and someone being taken for ransom.
"We will explore all and any angles. Once we move forward, we will start looking at his history and cellphone communications."
Anyone who has information about his whereabouts can contact the SAPS investigating officer, Captain Carolus Heyser, on 082 778 7241 or private investigator Colonel Luke Enslin on 082 222 5821/079 533 7069.