So I have lived in DSM for 3 years but still have my AZ DL (I have never changed it no matter what stat I have lived in, when I lived in CA or NV I just drove to AZ for my gun purchases). I know that if I take my AZ ID and my car title from IA I can get a handgun shipped and transferred to me but most FFL's dont want to deal with it and just say no. I know that getting an IA ID would solve all of this but my question/s center around private transfers.

Can an IA resident transfer a gun (I mean a pistol, I know that I can do long guns with my AZ ID) to me even though I reside here or is it all about the ID?

Just to be clear, I am not trying to get around the law I just dont want to change IDs as I may move back to AZ in a few years.

I think you're making life harder than it needs to be. Just change your ID. When we first got married my wife was a resident of 3 states in 3 consecutive years, and it never was a big deal to change.  

Just go to the Ankeny DL station with a bill in your name or whatever and become a resident.

Pretty sure the state considers your AZ dl to be invalid after 90 days of residency in Iowa. I could be wrong, but I seem to remember that from when I moved back from MN.

you have to get a Iowa id or license. Once you establish residency in Iowa, as Nandoz said, you have 90 days. you can, probably will, be cited for that. 3 years? that's not a good idea.

As everyone else said, get your local State ID / License, that should be fairly simple.

You might not have to actually change your vehicle registration -- I know of someone who was so annoyed by the DMV title-transfer requirements when they made a good-faith attempt to get IA plates (co-owner lived in a different state, DMV wanted in-person signature to move title to iowa), that they just ended paying the prior state to keep their vehicle registered for a decade till it died.

Alternately, you may be able to get a State ID + PCW without changing your government road use permission slip, but I'm not sure about that. Regardless, it's easier to just do it.

Get an ID and your permit. No DL is needed