The trench coat is an iconic design during transitional seasons that also does an excellent job of protecting you from the elements. Layer yours over everything from casual getups to more classic pieces.
If you'd rather not spend much, your best bet is this Forever 21 Trenchcoat. It's a terrific product, while not very expensive. Another savvy option is this Forever 21 Trenchcoat. While the price is competitive, be sure that this product will become a worthy addition to your wardrobe.