I found a used cva optima v2 50cal for $150 scoped and they are $300 new without scope. my concern is somethings wrong with it cause its so cheap but it looks mint but I couldn't crack it open cause it was locked. what should I check on this to make sure its not a lemon and sold because it was? to me $150 means they gave him $100 and somethings wrong with it. your opinion?