ShopBop has been my go-to e-commerce site since highschool. They have the perfect mix of high & low pieces, and their styles are so well curated. They rarely have any sales so their fall sale is a great opportunity to invest in the high-quality basics they stock.
It's also the best time to purchase any higher priced investment pieces like designer bags or shoes.
With code FALL20 you get 15% off a purchase of $200 or more, 20% off $500 or more, and 25% off $800 or more (hence my advice to use this time to purchase any big-ticket items!)