ITM Platform allows you to add users that do not have a license and we provide you with managing tools for your effort and cost planning, you can use however many non-login users you need.
When creating the user you need to select the "non-login user" option.
You may add this user into a project, make them a team member and estimate the amount of effort needed for each user in each task.
You can also designate hours for them ...
Then you can analyze the hours assigned to this user and know look at their profitability through reports.