A value driver tree for a simple operation can take as little as 10-15 minutes to get going. Builds with multiple models that are mapping larger and more complex streams of operations can take longer to build, as much consideration is needed at the design stage to ensure the best outcome of end-usability and visual coherence.
Other factors like the building proficiency and industry/context familiarity of the assigned builder can also play a large factor in build times.
One of the greatest strengths of Concerto is that you should never have to start a build completely from scratch. There are many options available that allow users to re-purpose, re-use, and re-cycle previous builds. The more your team builds over time, the quicker future build turnovers become!