During his long time in Bosnia (1883–1921) Vancaš constructed 102 residential houses, 70 churches, 12 schools, 10 palaces, 10 banks, 10 government municipal buildings, 6 hotels and taverns, and remodeled a series of buildings. Vancaš also produced drafts for church altars as well as drawings for the residential and ecclesiastical interiors. He exhibited his work at world exhibitions in Budapest (1896), Vienna (1898) and Paris (1900). In 1911, as a representative in Bosnia-Herzegovina Parliament, he submitted a resolution on the protection of cultural monuments in Bosnia & Herzegovina.