How much are taylor swift and brittney spears concert shirts?

So I'm going to see Taylor swift in concert on June 15 & was wondering how much her shirts are ? I'm going with my friend I'm wearing a cut hollister skirt with a flower design, a plain pink t shirt, cutte maurices sandals , and jewerly & for my hair im waving it. Is that good to wear to her concert? & I'm also going to see brittney spears July 6th with a bunch of my friends and was wondering how much her shirts are? Also what should we wear to her concert? We were think weird like have a fake nose piercing Jean shorts , and maybe make a shirt is that good ? Also what should we do with our hair ?