The Delancey Street Foundation (DSF) is evaluated as a 'buy' by the Nonprofit Investor, highlighting its successful residential self-help model for former felons, which requires minimal public funding and has a proven track record of graduating 18,000 individuals over 40 years. DSF generates a majority of its revenue from programs rather than donations, offers vocational training through profitable enterprises, and incurs a low cost per beneficiary. However, the organization faces challenges such as the absence of public impact studies, economic volatility affecting program revenues, and delays in financial reporting.