Re: adopting from another state question MA-AZ
I say GO FOR IT. My 6yo foster son has no relatives but DCS wishes he did. They would move mountains to get him placed with family somewhere.
The ICPC is complicated like the others have said, and it would take time and patience. I do not believe that 6 other kids is going to mess you up. Your cw could advocate on your behalf that the little guy would have built-in siblings, playmates and get lots of social interaction, while being with his biological family vs total strangers. That should be a huge plus in your favor.
Definitely call your local DCS and give them a heads-up and ask if there's anything you can be doing now to make the process faster. And like the other PP's have said--- you will need to do background checks, fingerprints and since those take awhile to come back sometimes, go ahead and start them.
Good luck! I hope you get your nephew!