quick rat question

[Bartman]

I am going out to get a rat for my bp. Long story short he wont eat rats, only mice, and I am going to see if he'll even take rats.

Questions

1) Am I supposed to get the same size rat that I would get if it was frozen?

2) incase my ball decides hes scarred and moves away and its time to take the rat out..will it be aggressive (the rat) and would it be safer to wear gloves incase?

3) I cant let my rents know theirs vermin in the house lol, so if i kept it in a closet (in a tank) would it make noise? Like it will squeek but to the point where they will hear it from downstairs or something?

thanks!