In The Hiding Place, what are Corrie's three visions in the last chapter?

There are a number of visions that are made real in the last chapter of The Hiding Place.  The visions are Betsie's, brought to fruition by Corrie in her stead.

One of the three visions referred to in the chapter title is realized by Corrie upon her release from Ravensbruck.  Betsie had envisioned before she died that she and her sister would be free by the new year, and when Corrie finally arrives in Berlin, she notes that "it (is) New Year's Day, 1945.  Betsie had been right:  she and I were out of prison".  The sisters are indeed free - Betsie is in heaven with her God, and Corrie has been released to go home to Holland.

A second vision of Betsie's is that she and Corrie will make it their mission to "tell people...tell them what we learned" once they are free, about the love and will of God through their experiences during the war.  Corrie becomes aware that this is "God's new work" for her, to spread his Good News by sharing "the truths Betsie and (she) had learned in Ravensbruck".  She becomes a speaker, "in churches and club rooms and private homes" in the years immediately after the war, and collaborates in writing a book about the subject, The Hiding Place.

At the meetings where Corrie speaks, she always tells about "Betsie's first vision:  of a home...in Holland where those who (have) been hurt could learn to live again unafraid".  Betsie had described this vision very concretely during her life, as a huge mansion with "inlaid wood floors inside, and a broad gallery around a central hall".  Corrie is stunned when a widow, Mrs. Bierens de Haan, offers her home for "this vision of Betsie ten Boom", and it turns out that the woman's estate exactly matches in detail the place that Betsie described.

Betsie's vision about a place where war victims can come to be healed is actually fulfilled threefold.  The Beje becomes a place for the "feeble-minded" in the city, individuals who have been "sequestered by their families in back rooms, their schools and training centers shut down, hidden from a government which had decided they were not fit to live".  Mrs. Bierens de Haan's mansion becomes a haven for released prisoners, who "find therapy in growing things" in the vast gardens on the estate, and finally, Darmstadt, a former concentration camp, is released to relief organizations to provide shelter for the countless homeless people in postwar Germany.  Corrie, who will help prepare Darmstadt for the needy, will make sure that, in honor of Betsie's vision, there are windowboxes at every window, and that the buildings are painted brightly, "the color of things coming up new in the spring" (Chapter 15).