Can you give me or direct me to finding out about
Contracting officers responsbilities
Different terms and conditions for the purchase
Where does GAO ruling become involved in this.
Based on additional clarification obtained from the submitter, the following information is provided—
1) FAR policy encourages the use of commercial items and services over non-commercial items or services. This preference was established as a result of the Federal Acquisition Streamlining Act of 1994. In fact, the policy at FAR 12.101
states that agencies "Shall acquire commercial items or nondevelopmental items when they are available to meet the needs of the agency." In other words, it's the contracting officer's responsibility to conduct market research and satisfy his or her agency's need with commercial items, whenever available.
2) Please see the ACQuipedia article on Commercial Contracting
for a basic explanation of difference between the acquisition of commercial items and non-commercial items.
3) Modifications can be made to commercial items to make them suitable for military use, and the items may still qualify as "commercial items." The commercial item definition at FAR 2.101
"Minor modifications of a type not customarily available in the commercial marketplace made to meet Federal Government requirements. Minor modifications means modifications that do not significantly alter the nongovernmental function or essential physical characteristics of an item or component, or change the purpose of a process. Factors to be considered in determining whether a modification is minor include the value and size of the modification and the comparative value and size of the final product. Dollar values and percentages may be used as guideposts, but are not conclusive evidence that a modification is minor"
It is up to the contracting officer to determine if an item can be considered as a commercial item, in light of the modifications discussed above.