COCOSHIPRetro One Piece Backless Bather Swimsuit High Waisted Pin Up Swimwear(FBA)

Im 5.2 150lb what size is best for me ?

Does this have a back or is it a tied halter?

I am 5'5 160 lbs. I'm really top heavy, but small legs, and small butt! I've read a lot of the reviews, but still not sure of the size I should get?

How is it fot long waisted ladies?