If you want to exchange the item you purchased.

[Jit833]

1) If you want to exchange the item you purchased, please specify what you like to exchange it for. And you are also required to pay the price difference if the price of the two items are not the same.



Can I phrase the sentence in such a way? Thanks for your help.

[billmcd]

1) If you want to exchange the item you purchased, please specify what you would like to exchange it for. And you are also required to pay the price difference if the price of the new items are not the same is more expensive. A refund will be made if the new item is less expensive than the original item.



Can I phrase the sentence in such a way? Thanks for your help.

I have provided a few suggestions, but your version would be understood by the average listener/reader.