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Another lightweight sportster due to gain value, the VX220 was Vauxhall’s rival to the Lotus Elise. It never quite reached the same level of success as the Elise, hence the lack of follow-up model.
Vauxhall’s loss is the used buyer’s game, though, as the model’s scarcity, barely aged looks and still razor-sharp dynamics mean it’s looked back upon fondly.
The lowest-priced VX220 on PistonHeads right now is less than £9000, and it won’t be long before the cheapest you can get is at least five figures.
Find out more: Used cars buying guide: Vauxhall VX220
Described by some as the greatest hot hatch there’s ever been, and widely revered as a pinnacle for Peugeot, the 205 GTi was available as either a 1.6-litre or a 1.9-litre.
As the oldest car on the list, numbers are dwindling - latest figures suggest there’s as little as 1400 left on the road.
It’s been in serious demand for quite a while too, so prices are already spiking. The cheapest non-project example on PistonHeads right now is £4250, so won’t be around for long.
Find out more: Ford Fiesta XR2i vs Peugeot 205 GTi - Throwback Thursday
Being one of the only cars left in production on Cap HPI’s list has got to mean something, although it’s been a while since Audi shoehorned a 3.2-litre V6 under the TT’s bonnet.
With models such as the TTS and TT RS following, the subtle 3.2 V6 is easily forgotten, although its cult appeal is now beginning to spread.
The Mk1 TT has just about reached the bottom of the depreciative curve, with long-legged examples on PistonHeads for well below £2000. V6 examples start at slightly below £4000, though.
Find out more: Audi TT | Used Car Buying Guide
History has been kind to the Z3 - at launch, it was dismissed as having style, but little in the way of driving thrills to back it up with.
But fast-forward 21 years and the BMW is far daintier and lighter on its feet than many of the flappy fabric and folding hard-top-models that have arrived since.
While 2.8-litre versions are the pick of the bunch, lower-powered versions are where the rock-bottom prices can be grabbed. £2750 is the cheapest on PistonHeads, and prices are guaranteed to rise in time for the summer.
Find out more: Used car buying guide - Rock-bottom roadsters for £1500
Face it - it was always going to happen. Citroën’s big barge from the mid-2000s sold in predictably tiny numbers but had the comfort and style to guarantee it modern classic status from birth.
Latest figures suggest there are 622 left on UK roads, which is surprising, given that the car peaked at less than 1000. Exclusive-trim, HDi-engined automatics are the most common.
The car’s scarcity is such that there are just two examples for sale on PistonHeads, priced at £4950 and £6740 respectively, with the cheaper of the two in rarer Lignage trim.
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The last Mini, produced by Rover in its dying years between 1986 and 2000, is another on the list, joining its numerous predecessors produced across the rest of its 41-year production run as a modern classic.
So loved is the Rover Mini and its otherwise-badged predecessors that prices have already risen, and bargain-basement, neglected examples are becoming ever more scarce.
Examples on PistonHeads can be had from around £6000, although with numbers falling and the few Rover Minis left falling into enthusiasts’ hands, prices are only going one way - up.
Find out more: 1959 Morris Mini-Minor road test - Throwback Thursday
No, not the first GTV - they’re already £40k-plus. The latest addition to the modern classics camp is the GTV produced between 1994 and 2004.
It’s little surprise that it’s gained modern classic status as 1) an Alfa Romeo, 2) a sports car and 3) the embodiment of 1990s zaniness, quad-headlighted and rear light-barred and all.
It’s another ever-rarer sight on UK roads, but cooking versions start at around £2000. Browse to your heart’s content on PistonHeads.
Find out more: To buy or not to buy? 2001 Alfa Romeo GTV for £2195
Firmly fitting into the ‘oddity’ category of modern classics, the Cube first made it to the UK as a grey import in its simply-styled second generation but was sold here officially - and unsuccessfully - between 2009 and 2011.
Funky, as-it-says-on-the-tin styling and trademark Nissan solidity (it was based on the Micra) means there are plenty left on UK roads.
So unloved was the officially sold version that the PistonHeads classifieds are rammed full of grey import second-generation cars, which start from around £3000.
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It’s not easy for the Mazda RX-8 - constant rumours of a rotary revival from Mazda (which have so far turned out to be a pile of Wankel), reliability woes and never quite reaching the cult status of the RX-7 render the RX-8 rather unloved.
These reliability woes have taken a good portion of RX-8s off the road, meaning the solid examples left have started to take off in price from the yellow-sticker figures they’ve sunk to in recent years.
RX-8s start from well under £2000 on PistonHeads, but a thorough mechanical check or a dab hand with a spanner is required if you’re in it for the long haul.
Find out more: Five brilliant cars that are worth the trouble - used car buying guide