First, let me caution, a book trailer video is only useful if it’s well done and most are not.
Second, you can’t just create one and then think it’ll take care of itself. You’ll need to push it and post it all over the place.
Third, don’t spend much money on this, if any at all.
There are good, reputable companies that create these trailers and if you feel technologically baffled or simply want a pro to film and edit the piece, use them. But video trailers are just a small piece of the marketing puzzle.
Do the following: