What does not come with this unit that I will need for complete installation?

Thank you for your question. Please review page 5 of the user's installation manual, found in the product specifications, for a complete description of what this system includes and the tools needed for a successful installation. While this system does include the necessary parts for a functional system, there are a few accessories we recommend for a more complete installation, such as the line set cover guard to both protect and hide the line sets. A surge protector is strongly recommended. There are also mounting options available for the outside condenser to keep it off of the ground. For more assistance, please give us a call at 1-888-377-2850.