It  is survey that from the world sell market to known Traditional landscapes.
And Local views. as well as  Modern or semi-abstract landscapes. sell best

By tracking sales investigate, This year's best-selling oil painting is Van Gogh's for whom  oil paintings and drawing include some of the world's best known, most popular and most expensive pieces. He influenced the current of in modern art. 

The second most represented artist in the best of Monet who the leader of the Impressionist movement,was able to capture the essence of impressionism

Certainly, if your favourite topic happens to be the same as the market's, you're choice well