I am attempting to file my taxes and I had a mini split system installed in my home as I wanted to be more energy efficient. However the company I went with sells them as a "package" and does not have an itemized break down of what each parts costs... So how do I determine the most expensive part if the company doesn't have or won't find the answer? The form says it wants the cost of the most expensive part. The person I spoke with said this is the "first time" someone has called and asked for a itemized breakdown of the cost. They said that all customers need is the invoice (which I have) as well as the QMID (which I have).