The Sales Message Builder will ask you questions and then dump all of your answers into the Sales Playbook which is where you will get your scripts.
You can spend as little or as much time as you want in the Sales Message Builder. But at a minimum, I would say that it would take at least 15 to 20 minutes to answer the bare minimum questions and get a script. But a good first pass at answering the questions might be 1 hour.
We have created a tool called Simple Start that asks you only 3 questions (technically 9 answer boxes, 3 boxes for 3 questions) and puts place holders in for the other questions and this allows you to create a script and use the system very quickly and you can then go back and answer the questions with place holders later. Here is a video that explains the Simple Start.