An area of the house drained directly into the ground, and the other line was collapsed but then the owner didn't really want to fix these issues or not with any expediancy when he did. 

A simple clean out of the drain tube and problem solved.

Top floor tenant in an up/down duplex clogs kitchen drain. 200 to clear the drain and 700 to repair the ceiling of the unit below.

The water came up through a storm drain and infiltrated the apartment. 

i had to replace a water line and that was 5K down the drain. 

Is the site flat and are their drain gutters running water away from the garage?

I call the county drain commission, they tell me they don't have any drains on the road, the road commission owns the only storm drain there. 

During inspection, we found foundation issue on concrete slab house, water turned off so can’t check for any leak, can’t find sewer clean out, can’t check if toilets are draining properly.

I’d expect my contractor to know the latter, so things like what size drain line to use but for things like set backs that would be better suited under the scope of an architect or similar role (and even they get it wrong some times too!).

After Toledo got about 5 inches of rain in a short period of time, my duplex started to have water come up from the drain in the basement floor, and out of the sewer drain in the basement.