Septic System and drain field

While doing one of my four mock inspections. I noticed this dwelling came without a septic system or drain field. Actually, it drained into a open ditch some 50 or so feet from the home. The owner is considering selling in the next year or so. My issue is: 1. No septic tank 2. No drain field and finally, if he does intent to sell does he have to install 1&2 to bring his home up to code.

Home was build in 1915
Location is in Michigan

Are you saying he is dumping raw sewage? Is this a cesspool? I didn’t know there was anyplace you could still have something like this. This must be a very rural area, huh?
Not to be a jerk but… you should learn how to do code research. There are a lot of different rules, but I’m pretty sure no place allows a system like this, so yeah he’d probably have to have a real septic system installed.