Issues with editing, need advice.

Hey all, hoping someone can help my wife with an issue shes having editing. she is using a MacBook pro with lightroom and topaz. For whatever reason she is running out of storage due to the raw file uploading, then lightroom making a copy, and then a save of the subsequent edited photos. She does have an external hard drive but I'd like to know if there is a way to do this without having to create so many files. Any help is welcomed and thank you in advance.