Whose responsible for the pipes to the septic.

However, the property has been robbed of the copper in the house (this includes the breaker box, some piping, and the electrical meters outside).

1) Make sure water pipes are in good shape inside and outside on the property.2) Have a good electrician handy that can add lights and reroute wires/switches.3) Concrete > Asphalt Did you work with any real estate professionals (agents, lenders, etc.) that you'd recommend to others?

After the inspection, the inspector found several items that needed immediate attention like drain pipe in crawl space was disconnected from house, new AC units were needed and a few more items that the seller actually agreed to repairing before closing.

Then when they find those hidden junction boxes or a pipe in a wall that needs to be moved they charge you 2-3x what it should cost hoping that because you already are contracted with them that you will agree to that number more easily.

The sewage piping from the homes has also been replaced.

Sewer connection shall comply with requirements for Depth of Flow (D) versus Diameter of Pipe (d) in sewer pipe as shown below:Diameter of Pipe (d)Maximum D/d8″ to 18″0.5021″ to 60″0.75Over 60″0.7513.

The risk to the systems would be frozen pipes and I don't think that would be much of an issue where you are.

It is currently PVC piping. 

When you reach the point of having assets with equity and/or cash flow to protect, and you implemented/exhausted all the other means of risk mitigation (insurance, umbrella insurance, proper property management, etc.) than you can complicate yourself with more elaborate asset protection structures.