1999 Mercedes-Benz SL320 Designo

In close to 10 out of 10 condition, this rare Designo with that unique paint colour is good news for the SL’s next owner; they’ll be buying a striking example of the R129 breed. Finished in special order Designo Sea Blue paint with a Saffron Nappa leather interior, it makes a lovely change from the uber safe, go-to SL-Silver that many others seem to wear.

We have test driven the car, during which it performed faultlessly in every respect and proved to be a totally refined, relaxing and enjoyable driving experience.

The V5 shows five owners in total have enjoyed this fully loaded car. Specification includes: wood/leather steering wheel; burred walnut root wood trim; cruise control; glass panoramic hard top; electrically adjustable steering column, seats (also heated) and wing mirrors, all of which seem to work as they should.

The mileage is currently showing around 54,300, which is still relatively little for one of these hugely capable machines, with only around 2,000 miles being driven in the last couple of years. Last January it had front and rear brake pads and sensors, replaced. The air conditioning system was drained and re-gassed, while the underside prepared and then treated with a clear Waxoyl product.

Think the exterior of this car looks good in the pictures? Well get our video below rolling and it’s clear that the static photography simply doesn’t do justice to that mesmerising Sea Blue paintwork. With the camera rotating an incredible depth to the finish is revealed, as the light hits it from different angles. It’s glorious, classy and enthralling in equal measure.

The nose is pleasingly free of stone-ships, we’ve been hard pressed to find a blemish on the rest of the car’s wonderful paintwork. The shine remains first class and clothes panels that are factory tight, with no telltale signs of any accident damage. All door shuts and sills are immaculately clean.

Finished in blue canvas the soft-top is in particularly good fettle, with no creasing evident on either the material itself or the plastic viewing panels (which at over £1k alone to replace is good news) - the former remains supple and its stitching still looks fresh, with no pulls. The hood mechanism works as it should, both lowering and raising the top smoothly and quickly.

The five-spoke factory alloy wheels all remain in great condition with no signs of corrosion or kerbing; there’s no lacquer peel and their corresponding Michelin Pilot tyres still have a good level of tread remaining.

Glass panoramic roofs are a two-man job both to fit and remove, and as such can get easily damaged over the years. This example’s remains in superb condition, with paint finish matching the high quality of the rest of the car.

Faults? You do have to look carefully, but we have spotted a tiny bubble on the nearside front wheel arch, just above the bumper - and the nearside corner of the front bumper appears to have had a very minor touch-up.

With most classics as a general rule of thumb, a neglected interior is usually a sign of a neglected vehicle. If you get yourself down to The Market’s Abingdon HQ, then you’ll find some very mild creasing to the driver’s seat bolster and, other than that, a very smart cabin.

The soft Nappa leather (which can be prone to wearing quickly) is mark free and supple, with no rips or tears. The burr Walnut root wood retains its lacquer and presents beautifully. With soft-top in place, its mark-free lining matches the rest of the cabin.

Personally we think a soft-top should always be down, but Mercedes-Benz has always offered SL owners an optional hard top and with this one in place, it’s a case of whoa… as the world above is turned into a moving canvas of art.

Peel your eyes away, bring your eyes back to the straight ahead and a quick check of the electrics (they’re complex big beasts, and got more so as production continued) shows that everything seems to function just as the seller says it does.

The engine bay is a sea of fairly uninspiring plastic, but its condition should leave you in no doubts that it’s been taken care of to a high standard. There’s no evidence of any leaks, or even a sign of an overly hurried oil top-up. Up above, the bonnet retains its temperature resistant factory fitted lining.

The underside still shows evidence of its quite recent and thorough rust proofing treatment with all panels, suspension components and brackets protected. There’s no evidence of any corrosion on the jacking points or peeking out from under the plastic sill covers, and similarly the wheel arches all appear lovely and solid.

The exhaust system is in good health and it’s nice to see that the engine under tray is still in place. The V6 starts on the button and is a fairly grunty little unit. The brakes pull nice and straight. Meanwhile the ride is tight, with no suspension clonks and a smooth automatic gearbox change. Best of all is that chassis, which was a turning point for the SL range and means it’s definitely more sports car than previous iterations.

The SL comes with both keys and its online MOT history shows a few advisories over the years, but the last of these were for low tyre treads in 2014. It comes with a few expired MOTs and some invoices, and its current MOT certificate was gained on 1st September  this year with no advisories – and so runs for another 11 months.

Included are all of the car’s owner manuals, and by all, we mean all – six in total! These are: interior, exterior, technical, driving, dealer directory and mobilo. As per Mercedes-Benz’s customer support overkill, some of these look as if they’ve never been opened. The service book shows a combination of main dealer and independent Mercedes-Benz specialist stamps.

Please visit the documents section of the gallery of this listing where you will find photos of the paperwork to support our claim that this car has been maintained to a very high standard.

This is a beautifully presented, rare R129 SL320 Designo that’s been properly looked after and its condition is testament to that fact. It is so good from every angle and there’s nothing apparent that needs attention; this baby just needs to be driven and enjoyed top-down this summer.

Should you wish to prolong the driving season then there’s the option of fitting that fabulous panoramic hard top. Once in place it provides an interior view almost as alluring as the car’s exterior finish.

Prices for this generation SL remain low. The R107 SLs took a while to take-off, but they’ve certainly shifted in the last five years and we feel it’ll only be a matter of time before the younger cars follow.

Do you look back at Pagoda SLs, and now the R107s, and think ‘I should have bought that when it was only…’ Well, that’s exactly where we’re at with its younger sibling!

We think this fabulous example will sell for between £15,500 and £22,000, which means the time is nigh to take advantage, and hoover up a top example at a very decent price.

Viewing is always encouraged, and this car can be seen here at The Market HQ in Abingdon; to arrange an appointment please use the ‘Contact Seller’ button at the top of the listing. Feel free to ask any questions or make observations in the comments section below, or try our ‘Frequently Asked Questions’.