North Carolina-based industrial property developer The Keith Corp. and its joint venture partner, Kiel Group of Bethlehem, Pennsylvania, last month sold the smallest of its muilt-building Hamburg Commerce Park in Shoemakersville, Pennsylvania, after leasing the newly developed 91,555-square-foot industrial building to Happy Returns, a UPS subsidiary and reverse logistics company that partners with e-commerce fims, logistics providers, and retail technology platforms to process exchanges and returns.