One Sales rebate threshold for multiple Item groups

Hello,

We have a scenario to setup Sales Rebate for Multiple Item Groups within the same thresholds. Is there a way we can achieve this by using advanced pricing? Please see the scenario below :

  

Item	Cat code 1	Cat Code 2	Item Group
Item 1	1	OT	ItemG1
Item 2	2	OT	ItemG2
Item 3	3	OT	ItemG3

Threshold         Amount

Quantity

5                         $1

10                       $2

Rebate thresholds to be defined for the quantitative sum of Item group codes 1 and 2 and not for 3. So, If the sum of ItemG1 and ItemG2 is equal to 7 then the customer will receive rebate of ($1*7) $7.

Thanks,

Rahul