AU question

[Jake0215]

Having a mortgage application in the semi near future I am thinking of adding my wife as an AU on a couple cards. Her credit file is pretty thin, she only has a car loan which is almost paid off on there. The only reason she got it in the first place was because of the sizable down payment. How many should I add her on to get the best mileage. I have two cards that are 4ish years old. Would those be the best? or the newer ones with the higher limits. I am good about util so the CL isnt really the issue, although the newer ones have the higher limits.

[Creditaddict]

For a Mortgage they probably won't care about the credit lines as long as that util is in check so if they purpose is to lengthen her profile I would do the 2 oldest with lowest balance.  She only needs 3 accounts, so the car would be one.

[AndySoCal]

 I would use the ones with the longest history.