Recently, the story emerged of the attempt by the Sultan of Brunei's brother, Prince Jefri, to build the greatest car collection in the world. It is chronicled in a new book on Rolls-Royce and Bentley, Kidnap of the Flying Lady, by Richard Feast and it tells how at one stage the company was delivering 70 to 75 cars a year - all specials - including half a dozen at £6m apiece.

The money eventually ran out but not before the prince, helped by his son Prince Hakeem, had collected between 2,000 and 5,000 cars, now housed in air-conditioned warehouses in Brunei. Not all were Rolls-Royces or Bentleys, but they, apparently, were his favourites.

It is a mad story, but also a sad one. There are many ways to build a collection but this surely is the wrong way. But it set me pondering as to what sort you could do for, say, £100,000, the price of a bedsit in London?

My own fantasy collection would have three criteria. One is that the cars can be used; two, that they in some way demonstrate innovation or excellence; and three, that they would have a reasonable chance of proving a good investment; a bit of pension planning here.

I would have three "musts", each illustrating engineering advances. One would be a Citroën Traction Avant, which, when launched in 1934, was perhaps the greatest single leap forward in car design history. You can get a good, early 1950s Light 15 for about £7,000. Another would be an early Mini. As well as all the obvious reasons, many of us have happy memories owning them in the Sixties. Say £8,000 for an original mid-1960s Cooper.

Then there has to be an American V-8, partly because of the utter reliability of these huge, lazy engines but also because of their place in the easy prosperity of classless 1950s America. The choice here depends is what is available: I saw a gorgeous early 1960s Lincoln convertible the other day, four doors and power top. But probably better an early 1960s Chevy Impala or Ford Galaxy, for these represent Middle America better. The problem will be the body, not the mechanics, so say £10,000 for something that has had the rust dug out.

There has to be a British sports car. For sheer purity of design, an early 1960s Lotus Elite, with its Coventry Climax fire-pump engine, would be best. But they come expensive and its replacement, the Elan, would be acceptable. Say £15,000.

I suppose there should be a Rolls or a Bentley, the older the better. The problem is getting value. The sensible choice would be a 20/25, around 1930. Better would be a Derby Bentley, built on the 20/25 chassis, but with a bit more power and a higher final drive. It should be possible to get something for £20,000. Leave a further £5,000 for tidying.

There should be an everyday car - the one you use to go to the supermarket - and that would be a Morris Minor, chosen for the sizeable industry that keeps these on the road and (a personal choice) the sound of the exhaust on the overrun. It should be the 1,000, with the 1098cc "A" series engine. A Traveller or convertible would be nice. Aim to pay at least £5,000.

That is nearly £80,000. My instinct would be to use the rest to buy history, a car owned by someone famous, provided it included the photographic support. Ultimately, people are more interesting than cars, aren't they?

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