M.L.
Go to Ross. Actually, Goodwill/Salvation Army and all sorts of thrift stores has tons of very nice slightly used dress pants for around $6. I have bought tons there, all from GAP, Banana Republic and nice brands like that. I would go to the interview in a pair of nice black pants and a blouse. Thrift stores usually have lots of really cute button ups too. Wear a pretty necklace or earrings to add style, you can find them everywhere for cheap. If you don't usually wear makeup, a little bit of mascara, powder to even your skin tone and some light lipstick or even lip stain will help you look pulled together.