There are a couple of options…as ever!
Example 1 – same action, taking the same time, done the same number of times, by several teams.
Each team has 10 people, they all do the work once a day and they all take 15 minutes. The team rates are different; $50, $75 and $100 per hour (x 10 as they are team of 10) – so 30 people doing this work once a day.
Example 2 – same action, takes a different amount of time for each team to do the work and they do different amounts of the same task. Within each team there are different rate – team leaders, etc.
From that I think you can see the various ways we can break this apart to get the accurate cost.
We have to ask ourselves who is doing what, how many people are doing the work, how long do they take and what is their hourly rate. If we have different answers for each of those questions we will need to represent each aspect with a node – even if it is describing the same thing.
You can view a sketch with these options modelled here: https://linqnz.linq.it/viewer?vt=bcEGE62fkypWPo7idnqHoA Look at the properties of the action nodes and the cost of people to see the impact these approaches have.