Leg AvenueWomen's Cozy Fleece Shark Halloween Costume

Im 5'3" and 145pd should i get a medium or a large?

I am 5'4" and about 130, would a small fit?

If this doesn't fit are there free returns or would I have to pay to return it?

I am 5’7” and around 150 pounds, my shoulder area is relatively thin though. Would a medium be okay or should I go up to a large ?