Thank you for submitting your item for appraisal. This appears to be painting depicting two white tigers in siberian landscape. Unfortunately the artist Josef Leitner is not listed anywhere. The "Original Brief für Gemälde" which certifies the authenticity of the painting was issued by a number of galleries, e.g. Mensing. Some of these galleries exclusively sold to american soldiers stationed in Germany, and in most cases prices where overpriced.
The estimate is based on similar paintings by lesser known artists sold at auction.