The plans for the Kehlsteinhaus were initiated in 1936 and it was presented to Hitler as a gift from the NSDAP for his 50th birthday on April 20th 1939 although the building wasn“t compleated until the summer of 1938. It is thought that the whole construction cost about 30 million Reichsmarks.
Although Hitler received the Kehlsteinhaus as a birthday gift he apperantly used it only sparsly as only 13 visits to the Kehlsteinhaus are related of officially. The lack of space there and the steeply falling rock faces all around brought on a feeling of dizziness and nausea in him.