4. Old Navy Rib-Knit Midi Skirt The Rib-Knit Midi Skirt ($20, originally $30) has an elastic waistband and a rayon-blend rib knit that makes it super casual and something that easily lends itself to everyday looks. Image Source: oldnavy.gap.com Rib-Knit Midi Skirt $20 from oldnavy.gap.com Buy Now NEXT GALLERY These 15 Spring Tops Look Pricey, but They're All on Amazon For Under $20 by Macy Cate Williams