No doubt your friend is sincere, but this points out an important fact about spiritual truth: If something isn't clearly taught in the Bible, then we shouldn't have confidence in it or build our lives on it.
After all, if God truly wanted to make everyone rich if they had enough faith, then why wasn't Jesus wealthy? Why weren't most of the early Christians wealthy? No one had a stronger faith than the Apostle Paul, yet he had to work as a tentmaker in order to survive. Few churches had a stronger faith than the little band of poor Christians in Macedonia, whom Paul commended because "their extreme poverty welled up in rich generosity" toward those in need (2 Corinthians 8:2).
It's true that God entrusts wealth to some people. But the Bible warns us not to be greedy, and not to put money in the place of God. Jesus warned, "No one can serve two masters.... You cannot serve both God and Money" (Matthew 6:24).
Urge your friend to make sure of her commitment to Jesus Christ, and then to seek His will for her life. Suggest she also seek practical solutions to her financial problems -- making a budget (and sticking to it), learning to live within her means, and so forth. If she does, she'll discover that God's promise is true: "God will meet all your needs according to his glorious riches in Christ Jesus" (Philippians 4:19).