You may operate in several ways. You can set up an office or may operate via online. Operating via online will be the least cost method and I recommend the same.
That depends on the business nature. Small-scale tourism business esp those have location advantage wise such as those in a natural setting (river, hills, nearby tropical forest, waterfalls etc) will probably invest less in physical development. Yet I found many local operators in Borneo (Sabah) Malaysia set their business profile using E-marketing platform and promoting their own place via website, social media, Instagram, youtube etc and appoint their relatives to run the business admin and operation. You can search on Kiulu Tourism, Ranau Tourism, Borneo Tourism, Sabah Tourism Board, Sarawak Tourism Board. You can locate the tour operator via their facebook profile and get first-hand research from them. The thing you needed is someone good in their dialects or Bahasa Malaysia