The T&M contract is a "hybrid" of fixed price and cost plus contracts. Its mostly used when the scope is initially poorly defined or when there is no defined end point for the work. It does not include an incentive like a CPFF. A CPFF also has a defined time period for the work.
I'm having a hard time choosing between T&M and CPFF.
I understand FFP is beneficial for buyer if scope is detailed and known and a risk for seller.
I generally understand that if your not too sure of the scope CPFF is the better choice. But now I'm getting examples in practice questions when T&M answers are contradictory. One says you use T&M when it's something new and hasn't been done yet before... And another site says don't use T&M because you don't know how much they will charge you for time. Very confusing.
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