A 1923 Leica sold for (US) $2.97M at an Austrian auction in 2018 (€2.4M or £2.15M).

The Leica 0-series had started at a price of 400,000 Euro and rose to a result 6 times higher. A private collector from Asia emerged as the winner from the exciting bidding war. The remarkable price certainly also reflects the camera's fantastic original condition. In 1923, two years before the first Leica was introduced to the market, Ernst Leitz produced 25 of this test camera, only three of which are known to still be in the original condition.

Leica Camera AG is a German company that manufactures cameras, lenses, binoculars, rifle scopes, microscopes and ophthalmic lenses. The company was founded by Ernst Leitz in 1914. The name Leica is derived from the first three letters of his surname (Leitz) and the first two of the word camera: lei-ca.

The Leica is particularly associated with street photography, especially in the mid-to-late 20th century, being used by many noted photographers, including Henri Cartier-Bresson, Ara Güler, Mark Cohen & Ralph Gibson. It was also used by many wartime photojournalists.

Leica cameras, lenses, accessories and sales literature are collectibles. There are dozens of Leica books and collector's guides. Early or rare cameras and accessories can have very high prices. Notably, Leica cameras sporting military markings are highly valued; this started a market for refurbished Soviet copies with fake markings.

More Info: en.wikipedia.org