ESS's program currently has only one option to add multiple indoor units to one outdoor unit.  The program was originally designed with the format when 100% of all installations were conventionally ONE outdoor, and either an air handler, or a furnace a coil.  Thus, this is why it is set to have four units.  

The temporary option is to add your indoor units as parts and list them in your proposal as "Special Parts".   They will still appear on the proposal, in your cost, as well as in the selling price.  

In the mid part of the year 2017, we will be introducing the option to add multiple indoor units.  Up to 9.  The program will even return an AHRI number.  Until we introduce this, the only option you have is what we have listed above.  
But stay tuned.  Exciting changes are on the way.  This feature is beyond design and is being coded.  I can't give you a roll-out date, but we are as excited to get it out to you as I am sure you are.  
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