The Mercedes-Benz W123 is a range of executive cars produced by German manufacturer Mercedes-Benz from November 1975 to January 1986. The W123 models surpassed their predecessor, the Mercedes-Benz W114, as the most successful Mercedes, selling 2.7 million units before production ended in the autumn of 1985 for the saloon/sedan versions and January 1986 for coupés and estates/station wagons. Following a slow production build-up during the first year, customers who placed their orders faced a lengthy waiting period of nine to twelve months. A black market emerged for the customers who were willing to pay more for immediate delivery. The slightly used W123 commanded about 5,000 Deutsche Mark premium over its original sale price. Like its predecessors, the W123 gained the reputation of being well built and reliable. Many taxi companies chose the W123, and they were a common sight in Germany. Reaching 500,000 or 1,000,000 km with only minor mechanical issues was common with W123s used as taxicabs. Once the W123 reached the end of its service life, they were often shipped to Africa and third world countries where they were highly esteemed for their ability to travel on rough roads and to not require frequent maintenance. W123 production ended in January 1986 with 63 final T-models rolling out. The most popular single models were the 240 D (455,000 built), the 230 E (442,000 built), and the 200 D (378,000 built). Design The W123 shares technical similarities with its predecessors including engines, steering system, and suspension system. The design is updated with styling cues from its larger sibling, Mercedes-Benz W116, namely wider ribbed taillights, horizontal headlamps, front turn signal indicators on the outer edge, and pull-to-open door handles. The interior is revised with a larger instrument panel, central round ventilation outlets, HVAC control panel and a single row of control switches in the centre. The instrument panel has three large gauges placed behind a single plastic cover. The manual HVAC control panel has three large dials with the left and right for individual temperature control and the centre dial for fan speed control. Air flow is controlled by two sliders (left for upper zone and right for lower zone). If the optional air conditioning unit was ordered, a temperature roll dial was fitted to the row of control switches. The automatic HVAC control panel is simplified with a single roll disc on the left for temperature control, a row of