I have a buddy who lives all alone.  He could really use a dog for companionship.  He lives in Arizona so it gets hot outside - he keeps the inside temperate.  He works four ten hour days a week.  His home is in the middle of a fenced three acre lot.

He thinks that it would not work to have a dog and lock it in all day.

I think he should install a dog door and let the lad come and go as he needs to.

One specific question:  How likely is it that other animals will get in the house through the pet door?

Generally I welcome suggestions on the situation and solutions.

RFID doors.

We have 3 dogs and two cats. We have  had a regular dog door for 9 years. 3/4 acre wooded lot.  No issues at all for me. I have had one mouse come in the door. It was a bad choice for the mouse. Now the dog's and cats have brought many presents in the house including squirrels. The husky mix dropped a squirrel in the wifes lap when she was sleeping.

Where I live I have 1K acres of forest behind me.  I have a 'doggie' door for my dog.  I have coyotes, deer, moose, turkeys, skunks, squirrels and chickmunks that I've seen on my property, never has anything tried to use my doggie door except my dog.

This is the door I use.  They make a number of doors for different applications.

This

My son has an RFID door and it’s slick!  It’s worth the $$$$.  It acts fast and opens/closes promptly.  Was visiting with our dog.  Our dog got locked out a coupl of time ‘cause she wasn’t quick/close enough.  Ain’t no vermin coming in the house unless it’s smelling your pets butt

Interesting.

I've had neighbor's cat, raccoons, and even an armadillo use my dog door.  I live in Houston.