If we could all accurately predict the markets we'd have quite a bit more cash in our pockets.
However, some people have such a close eye on demand and trends in their industry that they can give an informed decision on what's lined up to go up in value in the next 12 months.
Step forward Paul Michaels, the chairman of Hexagon Classics, who has a raft of super-exotic and very rare cars at his showroom in North London. Here he gives us a run down of what shot up in 2016 and tips five models he expects to rise next year with prices for the best examples.
Man in the know: Paul Michaels, the chairman of Hexagon Classics, prides himself on identifying the cars that are about to sky-rocket in value. He's selected five cars that will increase in price in 2017 and by how much
Paul Michaels, of Hexagon Classics says: 'After the rapid rise in values from 2012 to 2015, the classic car market in 2016 has been much more stable.
'There have been a few surprising auction results, but on the whole the days of huge growth are over and everything is a bit calmer.
'So what's done best? The Porsche 911 continues to prove a popular model. From the 993 to the 964 and 930 – particularly the rare and special versions of these models – values are strong. In fact, in many cases it's been cars from the 1980s and 1990s – the poster cars – that have performed best with steady demand.
'But if you fancy something older, certain Astons, Alfas and Jensens have done well. I've picked out some cars at a range of price points that have had a good 2016.
'What's in store for 2017? Well, one thing is for sure, this year has not been short of political shocks and that does tend to have a hangover. Buyers are much more cautious, so I think we can expect a steady year.
'I've picked out some cars that should return around 10 per cent, maybe a bit more.'
Paul Michaels said a bidding war over this 1995 Posche 993 GT2 at RM Sotheby’s auction in September was 'one of the most remarkable things' he'd seen all year. It sold for £1.8m - way above the £750k estimate
1. Porsche 993 (1993-1997)
Price range: £50,000 - £1.8m, Increase in 2016: +10 to 15%
PM: 'The last of the aircooled 911s, the 993 has always been held in high regard among collectors as it represents the last of the line – a 'proper' Porsche built at a time when the company didn't let the accountants compromise on the engineering.
'Prices have steadily risen with the best examples of Carrera 2, Carrera 4, C2S, C4S and Turbo appreciating by 10 per cent. Further up the range, the really special cars – Turbo S, RS and GT2 – have jumped at least 15 perc ent.'
With values for the iconic DB4, DB5 and DB6 hitting a ceiling, investors have started to look at the younger generation of Astons. The V8 Vantage has come into the spotlight as a result
2. Aston Martin V8 Vantage (1977-1989)
Price range: £300,000-£400,000, Increase in 2016: +20%
PM: 'There have been big rises for the DB4, DB5 and DB6 in recent years. But 2016 saw values level off. As older cars become more expensive and move further out of reach, values of younger cars come up – and the real movement in 2016 has been in the V8 Vantages.
'The late Eighties cars are in high demand as they're the more powerful X Packs. Prices currently range from £300k to £400k, up around 20 per cent on a year ago.'
Boycie's V12 Series III E-Type Roadster, the car that featured in the second ever episode of Only Fools and Horses, went under the hammer earlier this year. It sold for £115,000
3. Jaguar E-type V12 Series III Roadster (1971-1975)
Price range: £80,000-£90,000, Increase in 2016: + 15%
PM: 'There's a simple reason why V12 E-types have gone up so much in value in 2016: fewer and fewer people can afford the earlier Series I and II six-cylinder cars.
'Not so long ago, the Series III were £50,000 – they're now £80,000 and upwards. Add in a bit of celebrity ownership and some examples have even gone past £100,000: a 1973 Roadster used on the TV show, Only Fools and Horses, sold at auction in September for £115,000 so there's plenty of appetite out there.'
Michaels told us: 'Interceptors are very expensive to restore and put right, which is why buying an A1 car is the only real way to go. Do that though and you won’t look back
4. Jensen Interceptor (1966-1976)
Price: £55,000 - £65,000, Increase in 2016: +5 to 10%
PM: 'The Interceptor has always been regarded as the poor man's Aston Martin and as prices of the latter have risen, the muscular Jensen has been slowly heading upwards too.
'It's certainly had a good 12 months, with the very best cars gaining around 10 per cent with exceptional coupes commanding £55,000-£65,000 (rare convertibles are well in excess of this).'
There's evidence that in Italy Duetto Spider prices are moving even more quickly. If you can live with left-hand drive, buying one with the wheel on the 'wrong' side might be a canny move
5. Alfa Duetto Spider Series 1 (1966-1969)
Price: £25,000 - £30,000, Increase in 2016: +10%
PM: 'From British muscle to Italian elegance. Many 1960s and 70s Alfas have moved up in the last 12 months but the spotlight has fallen on the Series 1 Duetto Spider. It's the textbook glamorous but classless Italian roadster – and the fact that it had a cameo role in The Graduate adds even more to its charm.
Last year, you would have paid £20 to £25k for a good car, this year you're looking at £25k to £30k – but I'd expect this upward trajectory to continue into next year.'
Paul Michaels believes the Ferrari 365 is 'pretty much the only undervalued period front-engined Ferrari out there' It doesn't come cheap though at about £650,000
1. Ferrari 365 GTB/4 Daytona (1968-1973)
Price now: £600,000-£700,000, Potential increase in 2017: +10%
PM: 'The Daytona has shot up in the last 10 years but compared to the car it replaced, the 275, it has never really caught fire and last year it was pretty static.
'While an excellent 275 is worth around £2million, the same condition Daytona is not even half that. I have no doubt it'll follow the 275 upwards and I can see growth next year of around 10 per cent.
If you are contemplating a 928, the rare S4 manual is the pick of the bunch - just 7% of all 928s built were the S4, so it might be worth looking out for
2. Porsche 928 S4/GTS (1987-1995)
Price now: £60,000 - £90,000, Potential increase in 2017: +10%
PM: 'The 928 has been underrated for far too long and the reason for that is simple: it's not a 911. That's understandable as most people with £50,000-plus to spend on a classic Porsche generally want the 911 shape and six-cylinders hanging out the back.
'My advice is this, though: don't overlook the front-engined 928. It's got a long way to appreciate and 2017 could be the year it finally gets the respect it deserves. Pick of the bunch is the S4 manual, which costs around £60K for the best examples. It made up just seven per cent of total production so it's rare. Further up the range, the supercar-fast 928 GTS manual models are £80,000 to £90,000 and still rising.'
Prices for the top of the range models have increased in recent years - a good example of this carbon-roofed CSL is now worth around £70k, but standard models have time to appreciate
3. BMW E46 M3 Coupe (2000-2006)
Price now: £20,000 - £25,000, Potential increase in 2017: +5 to 10%
PM: 'The E46 M3 is without doubt one of the best BMW coupes ever made with a race-derived 3.2-litre six-cylinder engine and great handling. Prices for the rare versions have really accelerated in recent years with the carbon-roofed CSL now £70,000 (up from £50,000 around 18-months ago) but the 'basic' M3 still has some way to go.
If you're in the market, check the rear suspension (the subframes could crack and were replaced under warranty by main dealers) while the engine's VANOS valve timing system can play tricks.'
One for Italian Job fans: Paul Micahels predicts the Cooper S will increase in value by as much as 10% next year - a showroom condition example will cost up to £50,000 at the moment
4. Austin Mini Cooper S (1963-1967)
Price: £25,000-£50,000. Potential increase in 2017: +5 to 10%
PM: 'The original Sixties Mini is a classic that's always been in high demand. My favourite is the Mk1 Austin Mini Cooper S. They've jumped a good 15 per cent in recent years and I don't see that slowing down by much in 2017.
'Prices currently range from £25,000 for good cars to £50,000 for concours examples and you can expect that to go up by 5 to 10 per cent next year.'
The Lancia Delta Integrale made its name in Group B rallying in the 80s. It celebrates its 30th anniversary in 2017, which will ultimately see values increase
5. Lancia Delta HF Integrale Evolution (1991-1993)
Price now: £40,000 - £70,000, Potential increase in 2016: +5 to 10%
PM: 'Originally introduced late in 1987, it'll celebrate its 30th anniversary next year, which will undoubtedly lead to a surge in interest.
'The later Delta Integrale Evolution, Evolution II and Final Edition models are the most desirable. They're the fastest, rarest and most exotic. Prices currently range from £40,000 right up to £70,000 for the very best and with next year's anniversary, now seems like a good time to buy.'