For the vet visit, you can always turn the heat on in your car to be sure he is warm enough. I'm paranoid, myself, and took a heating pad on low in the car when we took our BP to the library for a kids' education presentation.

As far as body language, it's best to be cautious at first. It will take time to learn it. But generally, if they ball up, they are afraid/shy/don't want to be handled. But they usually stop doing it after getting used to handling, unless they really don't want to be handled.

Also, don't handle for 48 hours after feeding. If Cooper wants to communicate and you find yourself hard-headed, I am sure he will speak louder - with a hiss, balling, scurrying away, etc. I'm sure he will learn about you while you learn about him. It gets easier as you get to know each other.

Have fun and I hope the kids love him!