Expertise should be considered from individuals or groups with specialized knowledge or training in the following topics:  

Cost estimates are aggregated by work packages in accordance with the WBS. The work package

cost estimates are then aggregated for the higher component levels of the WBS. 

A data analysis technique that can be used in the Determine Budget process includes

but is not limited to reserve analysis, which can establish the management reserves for the project. 

Management reserves are an amount of the project budget withheld for management

control purposes and are reserved for unforeseen work that is within scope of the project 

Reviewing historical information can assist in developing parametric estimates or analogous estimates.

Historical information may include project characteristics (parameters) to develop mathematical models to predict total project costs.  

The expenditure of funds should be reconciled with any funding limits on the commitment of funds for the project.

A variance between the funding limits and the planned expenditures will sometimes necessitate

the rescheduling of work to level out the rate of expenditures 

Financing entails acquiring funding for projects. It is common for long-term infrastructure,

industrial, and public services projects to seek external sources of funds.