Looks like a fairly clean one - though the mileage is getting up there!

My concern would be; will start also show the signs of aging, like your own has? Mine is a 03, though a UK car, and the offside rear arch has bubbling, though not where else on the car is showing signs. Im hoping to get that sorted next spring, but my fear is, as soon as I do, more will appear elsewhere.

@[Dave]'s brother is selling a 525d - and I could be wrong, but it had a good bit of bodywork done reasonably recently due to a keying incident; might be a better one to consider?
Lower mileage, good service history, nicer interior IMO, better wheels, M5 mirrors, etc - http://www.bmwhaus.ie/forum/showthread.php?tid=6648