You'll likely need to invest 10-15 hours upfront.
Most past students have been able to get through all of the material (the Guidebook, and accompanying videos) in about 8-9 hours. It will take additional time to actually set up your Revenue Flow Map itself. This has taken past students 4-5 hours on average, depending upon how many breaks they need to do energetic clearings during the process.
It's time that you'll need to invest once, to continue reaping the benefits for a long time to come!