I store original manuscripts on high shelves for a while before I send them to Kent State University, which is the repository for my manuscripts in the University library Special Collections. They are on display sometimes at the Virginia Hamilton Conference there each year. The research depends on the novel or collection, etc. All of my books take research. There is always something I do not know or need to find out about.
Research is vital.
For the story collections, it may take six months. Novel research can take quite a long time. Research for M.C. Higgins, The Great covered details about strip mining, steel making and the open hearth method. Unions, mountains, country living, steel poles, hunting, swinging vines, skinning rabbits, underwater tunnels, and so on. So you see, research can be quite extensive.