Dad's chosen to live with a neighbor instead of moving to another state to live with one of us kids. Any guidance?

No, but it would scare the heck out of me! My first step would be to get (and pay for) an easy-to-use cell phone (Jitterbug comes to mind) for dad's exclusive use. Before I gave it to him, I'd program in my number and my siblings' numbers and show dad how to use it and have him practice it numerous times, so he's comfortable with it. And I'd leave written directions on how to use it. I'd also visit and try to convince my dad to move closer to family, if your other siblings are trustworthy. If you're having "control" issues with this "like a son", I'd have gigantic red flags going up everywhere and I'd want to move in to see what is happening.

I'd also do a background check on the neighbor, to see if he has any history of anything I'd want to know about (theft, fraud, elder abuse, assault, etc). Sorry to be so paranoid, but with elders who lose their sense of caution, it pays to be super vigilant. Please keep us posted.

This is a very scary situation and you need to act ASAP before this new "son" either gets control over your dad or is tempted to. I was in constant contact with my mother in the same town and spent almost every night with her at her home (I worked full time during the day) and she decided her paid caregiver should be her new daughter. The situation went from bad to worse and became a nightmare. If this could happen when I was physically seeing my mother, can you imagine what could happen when you aren't even in the same state?

You can only assess this clearly by going and seeing what is what. IMO,2K is far away, take some family leave if you are working or if you aren't working make arrangements and go and see him. I'd be hesitant to jump to conclusions, don't pull that trigger, first see for yourself. You don't need to be paralyzed with fears and what ifs, allay them by going to see him.

thanks for the comments. i do plan on going out to see him shortly, i try to be trusting, but worry also! and you are correct its hard to assess until i see for myself. i will keep you posted

Good Ideas! thanks so much!!!