We try out the £10,000 car wash

"The first time I got hold of the polisher, I lost control, slammed into the Mercedes badge and knocked it across the room. It was like, ‘S**t, how am I going to break this to the old man?'" For a company with a reputation for crafting quite possibly the most forensic paint job on the planet, it's reassuring to know it started from such humble - and apparently quite haphazard - beginnings.

Nabil Naamo, who co-founded Topaz Detailing with his brother, Mazin, continues: "When I first started detailing, I'd got hold of a machine polisher and I was working on my parents' old C-Class, and obviously it didn't go well."

Pictures: Greg White

This feature originally appeared in the November 2014 issue of Top Gear Magazine.

The brothers have spent much of their lives around great cars, listing a variety of Porsches, Ferraris and "just about every M Car imaginable". After getting hooked on detailing them, they had their lightbulb moment.

Mazin steps in: "We thought, ‘Why do our personal cars look this amazing after what we've done but there's nowhere we can go to get this service?' There was a niche, and we had to exploit it." This isn't just a case of giving tired exteriors a welcome refresh, but improving imperfect paint jobs fresh off the production line.

"The factory has a limit. They say: ‘Ninety per cent of customers are happy with this finish, and this is where we draw the line,'" Mazin tells us, as we stand around a freshly registered Ferrari F12 that's being machine-polished. While I've no doubt the guys providing the handiwork are accomplished in their abilities, hearing a screeching noise I'd normally associate with extreme DIY emanating from the panels of a £240k car is a slightly stomach-churning experience.

"It takes us 80 hours to refine and perfect a car's paintwork. It takes manufacturers about 100 hours to put a car together; they're not going to double their time of labour just for a small percentage of customers."

As a brand-new LaFerrari is trickled into the space behind the F12, and the screeching sanders graduate to a car worth five times as much, I have to ask how the world's greatest carmakers accept being told their paint isn't perfect. "We're not saying manufacturers are producing bad paintwork. We're saying that from a commercial point of view, they have to draw the line somewhere. But companies like us exist to take it to another level," Mazin says.

Topaz offers all manner of detailing services, but it's their full monty - which can cost more than £10k - that we've unofficially coined the world's poshest paint job. And it's got the air of a forensic criminal investigation.

The first tool to be whipped out is a ‘sun gun', a sharp projection of light that reveals nasty swirls, ‘holograms' or ‘orange peel' (a dimple effect that even brand-new cars, such as that F12, possess). Light reflections are key in the process, Topaz using many different bulbs in varying combinations to reveal every conceivable defect.

Next up is an electronic depth gauge to see how the thickness of the paint varies. Up to 30 measurements will be taken from each panel of the car (in this case, a searing blue Pagani Zonda Roadster), determining the consistency of the paint lacquer, and in the case of used cars, how original the panel is and how accomplished previous filler treatments have been.

An electronic microscope follows, complementing the depth gauge's report by revealing scratches the human eye can't spot. The results of these processes determine the tools used to level the paint, with a row of ominous-looking machine polishers lined up and ready. The forensic approach isn't just limited to stuff that plugs into laptops, though; each process gets its own colour of cloth, an approach Nabil happily admits is borderline OCD, but the charmingly labelled drawers add some (quite literal) colour to an otherwise science-heavy vibe.

Once the paint has been sanded down, the shine is brought back with top secret compounds the boys have developed themselves via trial and error on their own (and their family's) cars. Given codenames, the bottles' contents aren't even known to the staff spraying them.

Many customers may stop there, having laid out around £5k already, but the next step is the most beguiling of all to witness, especially as the freshly polished LaFerrari is wheeled in for the purpose. Paint protection film (PPF), which defends against stone chips, is hardly a new concept, but Topaz's is one of the priciest in the business and, they say, invisible; it's an adhesive plastic, with a flexible lacquer on top to give it the feel and appearance of paint. It self-heals, too: scratches that don't rupture the film fade away with heat (a spell in the sun is enough), a claim Mazin proves via a wire wool attack on an innocently bystanding supercar.

Topaz makes the film patterns itself, drawing out each panel of the car before reproducing it electronically to be printed out as adhesive and then applied. PPF fitter Gary Wood describes the process as "like trying to wrap up a football"; a flat, essentially 2D film has to be smoothly and perfectly stuck to complex 3D bodywork. And there can be no greater demonstration of complex than the painstakingly developed aero of a LaFerrari.

It's hard to take my eyes off Gary as he works; I watch him applying film to the front fenders and bonnet of Maranello's million-pound wonder, first spraying diluted shampoo to stop the adhesive plastic prematurely sticking before massaging the film around the supercar's surfaces, then spraying diluted alcohol to cancel the shampoo so that the adhesive can stick.

While most cars will typically take a day to fully wrap, the LaFerrari is set to take twice that. As the sun sets, a bunch of pizzas and doughnuts turn up. The guys are clearly here for a while yet to make sure the job is completed. The arrival of such overtly greasy food is at odds with the slickness of the operation it's catalysing, but all the more welcome for it.

It's easy to be a little sniffy about spending so much time and money on perfecting a car's shine - a 950bhp hypercar's especially - when any one of us, given the chance, would just want to drive the wheels off the thing. But Nabil reassures us when it comes to Topaz's typical client.

"We have a variety of customers, but most of them want to use their cars. This guy with the 964 RS (a gloriously restored example of Porsche's early Nineties lightweight hero) is driving it to Germany tomorrow - it's a 964, for God's sake, it's worth a lot of money, but he wants protective film all over the car as he's going to drive it plenty. Our customers use their cars; they're not shy." A splendid thing to hear.