Prevention of Arms Race Act of 2018 This bill restricts funding for the procurement or deployment of missiles banned by the Treaty between the United States of America and the Union of Soviet Socialist Republics on the Elimination of Their Intermediate-Range and Shorter-Range Missiles (INF Treaty). Before such funding may be appropriated, the Department of Defense shall submit to Congress a report that (1) confirms U.S. efforts to resolve Russia's violation of the INF Treaty, (2) identifies the ramifications of a collapse of the treaty and of a U.S. withdrawal from the agreement, and (3) addresses other related issues.