What companies are completely pimping out cars, old and new?

So many companies have been created over the past 50 years that have been explicitly made to modify, make luxurious, or reimagine how current cars could be improved and see how older car models would work with improved technologies of today. Even though today's cars are becoming more stunning by the year, older cars have their own beauty. Some companies focus exclusively on making the car, which has an old shell, into a vehicle that has features that any automobile would have today and even better. Arkonik, which is based in the United Kingdom, builds Land Rover Defenders with a customizable option for almost everything in the car, bringing the maximum cost up to around $150,000, while standard Land Rovers already sell for well over $80,000. This company takes an expensive vehicle, the Land Rover Defender, that is outdated for today's standards and makes it more comfortable and up to par with today's modern luxury standards. The customer can choose from a variety of interior options and exterior upgrades to make their defender last longer and feel more comfortable. 

An Arkonik Land Rover Defender A110

Some businesses focus on improving new vehicles in every way possible. Brabus is a company which improves almost every new Mercedes Benz AMG vehicle to even higher performance specs than the AMG's already insane specs. They also black out most of their car's paint jobs and add super luxurious interiors. They don't do all this for free though. For example, they give the S class an excellent treatment with a full luxury interior and a massive 6.2-liter engine and sell it for an insane... $400,000. 

The Brabus 900 Rocket S600

Porsches are especially popular among the performance tuning and reimagining community. Some well-known developers are Singer, Gunther Werks, and RUF Automobiles, which makes other models separate from making insane supercar 911's. Singer restores and upgrades Porsches from 1989-1994 that a customer supplies. They give the customer numerous options including an insane 390 horsepower engine and a basically fully customizable interior. They usually sell their cars with 300 horsepower since the 350 horsepower and 390 horsepower options are intended for off-road use only. They also give every car that they make a unique name like this Singer that they named the Dorset.

The Singer "Dorset" 911

Gunther Werks takes the 993 design Porsche 911 and makes a custom car from it. The vehicle, which is called the 400R, is made mostly from carbon fiber and other lightweight materials. They give the interior a  modern feel with a modern radio that has Bluetooth and improved audio. All of this improvement will put a HUGE dent in anyone's wallet, as is costs about half a million dollars. Not anyone can buy this premium supercar, though as they are making a limited amount of them, 25 to be exact. Some other companies that refurbish and make insane looking and driving 911's are Accumoto, an American based company and RWB, a Japanese based company that does similar things that RUF does. I would be ecstatic if I were close to any one of those bespoke Porsches. 

The "reimagined" Gunther Werks 400r

1986 Porsche 911 RUF BTR Slantnose (top speed:186 mph)  

1997 The RUF CTR2 (top speed: 220 mph)