Grouping of Billing Line Period for Covered Level

Hi,

How can we summarized a multiple billing line period for covered level in one line.

Here's a setup of a coverage product and its covered levels

Coverage Line - Gold Support 1 Year

 Charge - Activation Fee $1000

 Covered Level Asset: A Qty: 6

  Charge - Monthly Service Fee $100/Month

 Covered Level Asset: B Qty:5

  Charge - Monthly Service Fee $50/Month

Detailed billing summary will look likes this.

Period 1 Monthly Fee = $100 Asset: A

Period 1 Monthly Fee= $50 Asset: B

Our requirements is this

Period 1 Monthly Fee= $150

Thanks!