My dad needs care but his house needs to be cleaned up first. Is there a resource for caregiver standards?

Can you give more information about how bad it is? Is it full of animal feces or "just" rotting food? Is it embarrassing, or dangerous? I'm curious because my own home is hoarder-ish, and will be dangerous as my husband's abilities decline. I worked as a companion briefly in Massachusetts, and one client had a dog she could no longer take out. My employing agency was willing to let me work there!
Good luck. It's a tough problem, especially if he's unwilling to let his belongings go.