Readers expect you’ll get your facts straight.
Writing fiction? Unless it’s science fiction or fantasy, don’t think you can make up everything.
No mater how exotic your setting, readers expect you’ll not only set the scene with vivid details, but also that you’ll get those details right. When my wife recently read a novel that had someone in Denver drive south on a street that runs east-west, that spoiled the whole experience.
Another bit of fiction readers believe is that novelists have a research staff. In a Facebook post, someone complained a well known author “didn’t have the research team do a full job” on a recent title. “In the book it is said that a character goes [to] the Bethesda Naval Hospital for treatment but … it’s not call[ed] that anymore; it’s now call[ed] Walter Reed Joint Hospital.”
Never mind this reader used poor grammar and got the name wrong. (The current name is Walter Reed National Military Medical Center.) He expects each published book to be a team effort with every fact checked.
Even without a research department, you don’t have to work solo.
Even if (like most authors) you don’t have a research department, you don’t have to work solo. Check the acknowledgements in any major novel and you’ll see a list of experts the author consulted, and others who reviewed all or part of the manuscript. Often you’ll see names from the author’s writers group.
No matter how careful your research, you won’t make the bestsellers list without the support of a team — even if they’re volunteers.