Congressional Budget Office Cost Estimate: H.R. 625: Reporting Efficiently to Proper Officials in Response to Terrorism Act of 2017 [open pdf - 14KB]
"H.R. 625 would require the Department of Homeland Security (DHS) to report to the Congress when an act of terrorism occurs in the United States. The report would identify weaknesses in national security and recommend additional measures to improve homeland security and prevent terrorist acts. In recent years there have been few incidents of domestic terrorism, so CBO [Congressional Budget Office] expects that implementing H.R. 625 would require a small number of reports each year, on average. Based on the cost of similar activities, CBO estimates that providing the reports would cost less than $500,000 annually; such spending would be subject to the availability of appropriated funds. Enacting the legislation would not affect direct spending or revenues; therefore, pay-as-you-go procedures do not apply. CBO estimates that enacting H.R. 625 would not increase net direct spending or on-budget deficits in any of the four consecutive 10-year periods beginning in 2028."
Congressional Budget Office: https://www.cbo.gov