I agree about having him take SkyTrain and you picking him up there. Rental car facility will add unnecessary time. This coming from Phoenix resident of 23 years.

Freeway signs really are oddly confusing at Sky Harbor. They didn't use to be but recently they have been confusing me when leaving pickup on lower level in T4. It's very odd when they redid all the ramps and signage how they made it MORE confusing when before it was simple.