In the ‘Resource Details’ window (Application Base Setup -> Enterprise -> Resource -> Resource Details), it allows setting costs in General Cost tab per company and per site.  We can notice that there are different Resource General Costs associated with different Sites inside the same company.

However, in the Schedule of Work Estimating, when the Resource type is set to Project Resource, the ‘Site’ field becomes read-only, so the required Site cannot be selected.

The Cost Rate would always be the value associated with the Company instead of the required Site.

 

As the option to select ‘SITE’ exists alongside all other Resource Types within the above screen, then it would seem appropriate to enable this option for ‘Project Resources’ also. There is a requirement to be able to include a different rate per site within each company and then have that included within the cost calculation within the Schedule of Work Estimate.