What strategy does Lindner use in order to persuade the youngers to accept the association proposal? What is appealing about his argument ?

Mr. Lindner tells Beneatha and Walter that the Clybourne Park Improvement Association is willing to pay them more than their down payment if they will abandon their plans to move into the neighborhood. Beneatha, having suspected his intentions, is the first to react with sarcasm. Walter, taken aback, gathers his thoughts and tells the visitor to get out. Mr. Lindner, placing his business card on the table, leaves. Lindner is trying to stop a black family from moving into the white neighborhood. Mr. Linder seems polite and the "free" money might seem tempting but both the politeness and the money are tainted with racism, ignorance, and hatred.