Prapas’ name and phone number are emblazoned beside an image of a green-haired nymphet in a blue bikini so people can hire his vehicle, which functions like a taxi. On the front door is a pink cartoon bear, beaming cheerfully and waving welcomingly.

The paint job, by a graffiti artist, set Prapas back 50,000 baht (US$1,660) but it has been well worth it, he says. “Many people like buses with nice paintwork,” the 48-year-old explains. “They enjoy going on trips in decorated buses.”

Standing at a roadside where he has parked, Prapas waves at a colleague who drives by in an air-conditioned bus painted red. “His bus is more modern but doesn’t catch your eye,” Prapas says.

Competition is fierce among the owners of private tour buses in Thailand, and one way of standing out from the crowd is to put on a show. “You need to be like a peacock to be noticed,” Prapas explains.

Other tour bus owners share his view. Thousands of private long-distance coaches with custom paintwork traverse the countryside, appearing like flamboyant mirages on wheels as they barrel down highways among passenger vehicles that are painted mostly white, grey and black.

“These buses are a distinguishing characteristic of Thai traffic,” says Erik Cohen, 89, an Israeli social anthropologist who has studied the phenomenon of Thailand’s painted charter buses. “The decorations serve to display [the owners’] individuality among the mass of unmarked vehicles on the road.”

The trend got rolling two decades ago in small garages in parts of rural Thailand where older buses are revamped, retrofitted and redecorated.

Graffiti-style decorations were painted on some of the ageing vehicles to jazz them up, perhaps in imitation of the brightly painted small buses in the Philippines called jeepneys, which are fashioned from World War II-era US military jeeps.

The result has been an eclectic pastiche of eye confectionery inspired by street art on Thai roads. Some paintwork rivals the best graffiti murals decorating walls in Bangkok and elsewhere.

“It’s a commercialised form of pop art,” Cohen says. “Most designs are derivative, but they’re more refined than they were even a few years ago.”

The decorations emblazoned on private buses, and some trucks, come in a wide variety. Dominating current designs are characters from Japanese manga comics, American superhero films and popular video games. Many designs are replicas of movie posters, with the Fast & Furious series a particular favourite.

Occasionally, locals’ love of horror movies manifests itself. For his new bus, Sukij Klunsanoi, a 25-year-old driver, has selected a stylised, colourful tableau of slasher-film villains.

The phantom killer Freddy Krueger, from A Nightmare on Elm Street, with his leather glove of razor blades is flanked by the creepy ventriloquist’s dummy from Saw and Chucky, the evil doll from Child’s Play, who is laughing maniacally with a kitchen knife in each hand.

Near the back is another image of Chucky beside Jason Voorhees, the hockey-mask-wearing baddy of the Friday the 13th films.

“Some people think it looks scary, but I love it,” Sukij says. “Many of my passengers are students who love horror movies.”

Other popular themes include scenes from Chinese, Hindu and Thai mythology with religious undertones. Now and then, a Buddha image is painted overhead to provide positive karmic energy for a vehicle’s occupants, complementing the driver’s protective talismans affixed to the dashboard or hung from the interior rear-view mirror.

Decorations can also attest to the private lives of vehicles’ owners. “Some drivers want pictures of their cats or dogs painted on their buses,” says Nipon Komnan, 43, a freelance painter who works in Ratchaburi province, west of Bangkok, and neighbouring Nakhon Pathom. “Or their kids like Doraemon, so they ask me to paint that.”

The semirural area where Nipon works is one of the country’s two main bus-painting hubs; the other is in Nakhon Ratchasima province in Thailand’s agricultural heartland.

Nipon says he has lost count of the number of vehicles he has painted since he started out two decades ago. When he drives his car (which he’s left modestly undecorated), he frequently sees his handiwork on the roads. “It’s nice to know my paintings are still around years after I made them,” he says.

Like most bus decorators, Nipon employs a combination of stencilling, airbrushing and freehand painting. More elaborate designs can take him several days or even weeks to complete.

Even often-rendered images like superheroes can be taxing if a customer wants them with more lifelike features, including wrinkles and beads of sweat.

“The more realistic paintings need to be, the harder it is to make them,” says Patthanan Chaiyaboot, 35, who runs a business with her husband for decorating and outfitting buses and other vehicles.

They’re also more expensive. Yet a heftier price tag hasn’t deterred Warot Promchawi from ordering a high-fidelity rendering of the Hulk for his concrete mixer truck, which he uses to earn a living as a freelance contractor.

“If I had a normal-looking mixer, why would people want to hire mine and not someone else’s?” he says. “Now my truck will stand out.”

To be even more noticeable, many owners festoon their buses and trucks with chromium bling. Their vehicles resemble wacky anime versions of the road warrior conveyances in the Mad Max movies.

Dozens of mirrors, large and small, are mounted on both sides in protruding clusters, while covering the front are rows upon rows of headlights, spotlights and fog lamps.

At the back, outsize mud flaps are printed with paintings of Mexican bandits or American actor Al Pacino from the 1973 Hollywood drama Serpico.

Many buses get glammed up on the inside, too. Upholstered ceilings are inlaid with backlit acrylic plates laser-printed with flowery patterns and edged with vivid LED lights. Speakers and disco lights complete a discotheque-style feel in the passenger compartment.

“During long rides many passengers like singing, dancing and partying,” Patthanan says.

Supab Suksawat can confirm that. A villager who lives in a southern province, Supab likes going on days-long trips around Thailand with friends and colleagues in rented tour buses.

“When the music starts and the twinkling disco lights are turned on, we all get up and dance,” the middle-aged woman says. “It’s so much fun. Even the bus begins to bounce as we dance.”

Yet such revelry isn’t without risks in a country with one of the world’s highest traffic fatality rates. Each year more than 20,000 Thais die in road accidents.

The bus’ driver reportedly didn’t hear the approaching train because of the blaring music of a spirited passenger party in his vehicle.

Superman, Spider-Man and Captain America may have superpowers in movies, but painting them on buses won’t help protect occupants, says Suriya Klaewtanong, 45, a petrochemical engineer who has found a new calling as a successful bus designer and decorator.

He pioneered American superhero designs in Thai bus paintings in 2008 when the first Iron Man film was released. “If you do a nice new design, other people will copy it, so you have to keep innovating,” says Suriya, who employs 70 people, including freelance painters, at his hangar-like garage in a town in Ratchaburi.

Yet times are changing for Thai bus art. Many new custom-built buses assembled from factory-made parts in workshops like Suriya’s boast futuristic looks with outsize looping windows around their sides, leaving little room for larger murals.

Nonetheless, bus painting is here to stay. “They keep on painting buses all over the place,” Suriya says. “Just around here there are a dozen other businesses that do it.”