Home › Blog › Buying Guide › What Do Buyers Look for Before Investing in a Pre-Owned, Used, Secondhand, Surplus CNC Equipment Before Purchase DN SOLUTIONS (DOOSAN) DNM 4500 CNC Vertical Machining Center made in South Korea When considering buying a pre-owned / surplus CNC vertical machining center like the DN SOLUTIONS / DOOSAN DNM 4500 (made in South Korea), you want a systematic inspection and evaluation approach....