If it looks like it 1) holds water instead of draining it into the ground or 2) is in bad shape, consider that in your purchase.  

When the drain is clogged the PM can't send their maintenance person by so you'll be paying someone $99...and have to coordinate it.  

If that's the case, you may have to invest in an interior drain tile w/ another sump pump to help keep up w/ the water flowing into the basement.https://www.statefarm.com/simple-insights/residenc...Not sure if you're familiar with this, I came across this sump pump powered by the house's water pressure.

No one would re-wire copper wires or re-plumb the DWV system unless these systems needed, assuming DWV is PVC and drains properly.

You could have a perfectly drained home but just joists from a past termite issue.

Hate the brain drain of it all, but nice to be able to compete with peer states. 

It increases runoff and results in waters rising faster than draining.

If there is a leak in the freezer it could very well be that there is an ice dam build up and/or frozen condensation drain line that is not allowing the water from condensation to make its way into the condensation tray.

I noticed that the landscaping was such that water would improperly drain tward the house.

One of the things that holds investors back is not having enough cash, and you are about to throw some down the drain in my opinion.