speaking as a practicing bankruptcy attorney . . .
when asked to do this, ASSUME the the person will default and that you will be required to pay.
Is this something that you are capable of doing, or will you be coming to see me in a professional capacity?
Next, is this something you are willing to do for this person?
The bank is an expert; you are not. When they require a cosigner, it is because by objective analysis, this person is a very high risk of not paying.
There are situations in which you see why this person has changed, and will stick your head on the chopping block for them–but realize, this is what you are doing.
And what will happen to your relation with this person?
Another way to look at it: is this an amount that you are willing to give this person to help him put his life back together? If so, sit down with him, and kick in the extra to send him to a Dave Ramsey or similar course, and do it. If you don’t have to pay, wonderful–but arrange your finances around paying.
hawk