Congressional Budget Office Cost Estimate: H.R. 3542: Hamas Human Shields Prevention Act [open pdf - 86KB]
"H.R. 3542 would require the President to identify and impose sanctions on foreign people or entities affiliated with Hamas that he determines have used civilians as human shields or have provided, tried to provide, or facilitated the provision of material support to that terrorist organization. The bill also would require the President to direct the United States' Permanent Representative to the United Nations to use the voice and vote of the United States to secure support at the United Nations Security Council for multilateral sanctions against Hamas for their use of human shields."
Congressional Budget Office: http://www.cbo.gov/