How do I create a proposal with multiple capacities? 

Complete the "Customer" and "Survey" portion of the Proposal App to arrive at the "Proposals" tab 

Next select your system type, followed by the capacity for the first proposal.

Next drag a bundle to any of the proposal options.

To add a bundle with a DIFFERENT capacity, simply select the new capacity you would like to include. 

Then drag the bundle with the new capacity  to the same proposal to offer multiple systems, or to an empty proposal option, and you have a multiple capacity consultation!