Short answers, pulled from the story.
Leonid Brezhnev used the phrase Common European Home during a visit to Bonn, West Germany in 1981. This early usage likely aimed to sow discord between the United States and its European allies.
Mikhail Gorbachev delivered his main address in Prague declaring an overriding significance to the European course of foreign policy. He stated resolute opposition to dividing the continent into military blocs facing each other.
General Secretary Gorbachev arrived in Bonn on the 12th of June 1989 for private talks with Chancellor Helmut Kohl. The following day Kohl and Gorbachev signed a joint declaration supporting national self-determination.
Gorbachev spoke before the Council of Europe in Strasbourg on the 6th of July 1989 regarding the philosophy of restraint. He declared that the concept rules out the probability of an armed clash or use of force against alliance.
Robert D. Hormats saw the nascent European Community primely positioned to take on the role of a Common European Home. He cited its moral, political, social and economic strength as key factors for success.