Unless it's a husband-and-wife situation (or another equivalent long-term relationship with the expectation of permanency, etc), I think the AU usage ought to last exactly as long as it takes to get those 2 or 3 cards and maybe a loan, and get a month or two of timely payments going. Then cut the apron strings.
Both parties are at risk in an AU relationship, and the only way that it becomes close to being palatable is if the two people are partners in running a household and are using the AU card as part of the family financial plan. Otherwise, the AU is vulnerable to the cardholder getting behind on payments and so forth, and the cardholder is vulnerable to the AU or someone close to the AU going ahead and using and abusing that credit, even if it was understood that this wasn't supposed to happen.
Grab the good out of it, and then skitter away!
* Credit is a wonderful servant, but a terrible master. * Who's the boss --you or your credit?
FICO's: EQ 781 - TU 793 - EX 779 (from PSECU) - Done credit hunting; having fun with credit gardening. - EQ 590 on 5/14/2007
