On an otherwise ordinary-looking, potholed street in the district of Victoria Island in Lagos, Nigeria, is a stone encrusted gate with personalised initials. In the garage beyond, draped in protective covering, is a fleet of eight sports cars that include Lamborghinis, Ferraris and Porsches.

"On a typical weekend these guys head to the boat club to board a private speedboat or jetboat to Ilhasa," said Michael (not his real name), a regular at the house of the Nigerian high-society figure, referring to an exclusive beach known as Millionaires' Playground, an hour away from the polluted lagoons of the commercial hub. "There'll be girls in bikinis playing volleyball, barbecues and parties all night.

"On the right Saturday, you can bump into [Africa's richest billionaire, commodities trader Aliko] Dangote having a beach party at Ilhasa. If you're a so-called big boy in Lagos and you don't have a beachhouse, you're kind of whack," Michael concluded, sipping a Hennessey on the rocks inside an exclusive Lagos club.

Welcome to the charmed lives of a tiny elite that make up the super-rich across Africa. While millions live in crushing poverty, breakneck growth across the continent has expanded wealth beyond the traditional circle of government workers – for a lucky minority. This is the market the makers of Porsche hope to tap into, choosing to open its latest showroom on the continent – the first was in South Africa – in Nigeria. In an ultra-modern glass and steel building, the auto maker unveiled its latest Carrera and 911 models. "It's the sports car that can still be used everyday," Africa Porsche director George Willis said.

About 200 Nigerians own the luxury cars, each costing up to $180,000, brand manager Michael Wagner said. Porsche's 4x4 Cayenne is by far the most popular model imported into Africa, suitable for still poor roads. In Nigeria, there are plans for a Porsche racetrack and a Porsche club "where people get together and compare, and go out on drives together", Wagner said, shortly after officials revved the latest Carrera model for reporters and thrilled onlookers, some posing for photographs in front of the gleaming black car. In the sticky heat outside, an employee said owning one of the personalised Porsches he was washing would be "a dream. But I only earn $120 a month," he shrugged.

While Victoria Island is home to some of the planet's most expensive real estate, most of Nigeria's Porsche sales will come from Abuja, the makers believe. In the moneyed capital city, where wedding-cake mansions overlook smooth cloverleaf highways, wealth is a more conspicuous status symbol.

"There's a big market here. For example, I have a Bentley, a Porsche and a Ferrari, so I can easily buy another brand-new one," said one businessman from Abuja who sponsors golf tournaments as a hobby. But he added: "People don't travel by road anymore, they go by air. So the Ferrari in the garage hasn't done 500 miles in three years."

Others brands are also clawing out a slice of the super-rich pie in Abuja. Government fat cats and a new breed of young entrepreneurs flock to the boutique of the designer Chris Aire, a Nigerian who is based in the US. The "king of bling" designs for the likes of Oprah Winfrey and Angelina Jolie, and opened his first boutique in Africa in December.

Expensive spas compete to offer facials that smother pure gold leaf on customers' faces, and gleaming malls are popular with affluent shoppers. There are other signs of the super-rich, even as Africa's inequality gap yawns. Porsche is already planning a showroom in the Angolan capital, Luanda, similarly awash with petrodollars and ranked the world's most expensive city 10 years after coming out of a 27-year civil conflict.

Over in the Ivory Coast city of Abidjan, once nicknamed the "Paris of Africa", billboards advertise French perfumes and Rolex watches. The city is home to a glass-front luxury brand-only boutique, Zino's. "Ninety per cent of our customers can walk in and spend $35,000 in one visit without thinking about it," store director Jean Miguel Darde said.

While a top-end market is growing fast in Africa, Asia and the Gulf states still account for the lion's share of Porsche sales. In Nigeria at least, the road ahead won't be without bumps.

"Young guys with money need cars they can drive every day to show them off. There are cars that can survive potholes and there are cars that can survive potholes in Lagos," said a Nigerian oil worker. "Porsche are going to have to adapt to Nigerian terrain, the same way as Mercedes did [by marketing more off-road vehicles]."

Shopping abroad remains the ultimate social status badge for many. Maddie, 33, from Abuja, who runs a boutique in between having gold-leaf facial treatments, said Dubai was fast edging out European capitals as the destination of choice. "I travel every two months but I couldn't cope with going to London with my two children alone when both their nannies' visas run out. They don't need visas to go to Dubai, so it's easier," she said.

Still, luxury brand retailers are likely to flourish in a country where wealth is traditionally seen as a benefit to the community. "If we didn't have such terrible leaders only concerned with buying themselves things, everyone in Africa would be rich enough to buy designer clothes for themselves and all their friends," said Christina Akinjola, an unemployed secretary, as she stocked up on fake Chanel bags in the car park of a Lagos mall.