You can get 30% off sitewide at Beginning Boutique with the code SALE30 until the 19th of August.
MinkPink Secretary Denim Dress for $83.96 vs. $119.95 at The Iconic
It's available in all sizes except S, made from a mid-weight denim material in a mid blue wash. This midi length dress features a high neckline, capped sleeves, a fitted waist, all over fitted silhouette, an open back with three snap button closures at the nape of the neck and an exposed zipper in the skirt and a small split at the back hem.
You can get dresses on sale as well - denim dresses work out at around $35 a pop and other styles I liked and are available in all sizes would drop to roughly $40. These prices are similar to what you can get elsewhere at the moment (ASOS, Boohoo, etc.), however if you like BB's collection better, it's a decent deal.