The situation
Not every job starts with a fixed contract price. Some projects are billed by hours, materials or completed work. The immediate priority is to understand what the job has cost so far.
Create the project without a fixed budget
In Project Room, leave the optional contract budget empty or at zero for the time-and-materials style of tracking. Instead of subtracting expenses from a contract value, the project accumulates recorded costs.
Keep records consistent
Add project expense rows as costs become known. Where suitable, import time rows from CSV rather than retyping everything. Store relevant supporting documents with the project to make later review easier.
Review and report
Use the financial overview and available project reporting to review the running cost total. Before billing, check the underlying records and make sure any invoicing rules or taxes are handled by your usual business processes.
When this is useful
This approach helps service businesses, contractors and small teams who need a straightforward view of costs before a final invoice or project review.
Illustrative workflow, not a financial or accounting recommendation. Availability and exact screens can vary by application version.