Subcontractors as resource

Please help... 

So I went ahead and set up all of my activities with dates, predecessors, successors etc for a project which is a construction contract where I have some of the work that is self performed, some where I have vendors providing materials, and subcontractors who have provided me their quotes. Next, I set up all of the vendors and subcontractors as resources. I would like to know if there is a way to load the costs (quotes) from each subcontractor into the activities they each perform.

For example: 

Subcontractor A - Quote Amount: $900,000

Activity A - 12 days

Activity B - 12 days

Activity C - 26 days

Activity A should be only 20 percent of the total quote.

Activity B 25%.

Activity C 55% of the total dollar value.

I am stuck at how to proceed. Please help...

Thank you,

Eddie