JFK damaged his back in the second world war and was advised to buy an Appalachian oak-framed rocking armchair from the P&P Chair Co. He became so attached to this type of chair that it was even brought on to Air Force One. When Jackie Onassis’s collection was sold at Sotheby’s in 1996, two chairs were sold for nearly $500,000 each. Photograph: PR
This is one of only three almost life-sized sculptures, made of gilt porcelain. The Museum of Modern Art Chicago paid $5.6m for it. In light of Michael Jackson's death, it is likely that it will maintain and even increase in value in the future. Photograph: PR
Diana owned a red W-registered Austin Mini Metro before she was engaged to Charles. The car is now in the Museum of British Road Transport. The value of the same model today without royal association is under £500; Diana's car is worth £30,000-£40,000. Photograph: Phil Talbot/Alamy
A designer chair was used in the Diary Room of the house during Big Brother 3. All of the contestants from BB3, including Jade Goody, sat on this chair. If you are an ardent fan of the show, the £4,000 paid at auction after the series may seem pretty modest. Personally, I wouldn't touch it with a bargepole, as I don’t see artefacts from this sort of programme holding their value in the future. Photograph: Channel 4/PA
The ultimate racecourse, beloved by millions for nigh-on 100 years. All the great and the good involved in the ‘sport of kings’ would have passed through these hallowed portals. The entrance's value as scrap would be less than £5,000; it's value when put on the market is £280,000. If you are buying a sport-related object it is best to go for a major sport which is likely to endure and grow for at least the next 100 years, for example golf, cricket or football. One of the best-performing sports has been golf, largely because so many wealthy people around the world are passionate about the game and its historical artefacts. Photograph: Scott Barbour/Getty Images
Wacky but true: 25 years ago, Michael Jackson’s hair was ignited accidentally during a photo shoot. A canny producer smothered the blaze with his coat (Armani, of course) and gathered up the smouldering locks. The minute Jackson died, a company called Life Gem announced that they had bought the hair and would be making a limited number of diamonds using his DNA. The price is likely to be sky high when the diamonds hit the market. Photograph: PR
This car was manufactured in 1965 and was fitted with a double bed, TV, telephone and fridge in 1966. It was originally matt black, but in 1967 The Foot, a Dutch team of Gypsy artists, were paid £2,000 to paint the car psychedelic colours. This caused an elderly woman to attack it with her umbrella, screaming: ‘You swine, you swine, how dare to do this to a Rolls Royce?’ Nevertheless, by customising it, John Lennon turned the car into a coveted collectable. It was sold in 1985 to Jim Pattison Ripley’s Believe it or Not museum for $2,299,000. Photograph: PR
When Napoleon died in St Helena 1821, his servant Ali and his priest Vignali claimed to have removed some of his body parts. Vignali’s descendants sold his collection of Napoleon items in 1916, including a ‘mummified tendon’. In the 1960’s at Christie’s, his penis failed to sell, prompting the tabloid headline ‘Not tonight Josephine!’. It eventually sold at a Paris auction house in 1969 for $38,000. I expect it would make more than that today, but some would say it is high time it is laid to rest ... Photograph: PR
A two-inch square is all that remains of the cake made to celebrate the wedding of former King Edward VIII and Wallis Simpson in 1937. It is wrapped and inscribed, and was estimated at $500-1,000 when it was sold at Sotheby’s in 1997. It actually went for $29,000! When the buyers, Mr and Mrs Yim, were asked if they were going to display it in their home, Mr Yim quipped: ‘Well, we sure ain’t going to eat it!’ Photograph: Martin Poole/Getty Images/Digital Vision
One of the last sales I conducted at Sotheby’s in Chester was the Auchterlonie golf club collection in 1991. This was a unique group of 23 golf clubs collected by Willie (who won the Open in 1893) and Laurie Auchterlonie from the Royal and Ancient club at St Andrews. Their trick was to ask each winner of the Open to give them a golf club as a memento. Twenty-three clubs later, I sold the lot for $1.4m. The names of those 23 Open winners are now obscure to all but the most dedicated fans of golf history. The heroes are the Aucterlonies, who were canny enough to see the potential value in forming the collection in the first place. Photograph: PR
