Change orders are priced three ways: lump sum (fixed price for well-defined changes — preferred for client cost certainty); unit price (agreed rate per unit of measure times actual quantity — for changes where type is known but quantity is field-determined, like rock excavation at $X per cubic yard); or time-and-material at the contracted markup rate (actual labor hours at contracted rates plus materials at invoice cost, plus the overhead-and-profit markup stated in the original contract — typically 15–25% on labor and materials). The T&M markup rate is defined in every RainFire Builders contract at execution — never negotiated after work is performed when the client has no leverage. RainFire Builders uses lump sum pricing wherever the scope is defined to give clients cost certainty on the change order amount.