Is $8,500 to remove mice and mouse-proof home a fair price?

My main concern with poison is accidentally killing a cat or chicken if they ate a dying mouse. I'm on a half acre of land. I'm newly pregnant with my 2nd child and really don't want an indoor cat. I've been told to make bucket traps for weeks. I'm also considering flying out to help mouseproof. I don't understand why they can't patch the holes from underneath the house, especially since they said the majority of patching will happen there. I'm also wondering if mice chew through expanding foam, as that was my idea, coated with powdered ghost pepper. I know for a fact that the entire underneath of the house is open in several spots in the back. My cats are lazy and need to hunt more; I've told my sister to feed them half as much in the morning only. My sister threw a dead mouse out last night that was still partially attached to the snap trap and one of the cats carried it away. I'm wondering if cats know if a newly dead mouse was poisoned.