Home-decor creator Kristen McGowan (@KristenMcGowan) is making a strong case for secondhand shopping after turning thrift-store and antique-mall finds into polished room displays. The new additions look warm, layered, and intentional rather than like leftovers from someone else's house, due to McGowan's efforts. What happened? Instead of ending with the shopping trip, Kristen's YouTube post shows her finds back home, where she demonstrates how …