Try looking into zillow/Redfin and see what your potential rents you can get near the neighborhood by filtering the bedrooms/bathrooms of the intentional property that you are planning to buy.

Then I calculate that replacing the roof, HVAC, and remodeling bathrooms/kitchens would cost $400,000.  

It sounds like the bathroom would be added to your primary residence so it partially depends on when you would look to sell the home or start otherwise renting it out.

In order to minimize the potential for mold growth in the property, Resident(s) must: *Keep Premises clean, especially the kitchen, bathroom(s), carpets and floors.

You may have heard Lake Michigan has risen six feet in the last ten years, then it dropped three feet recently, yet somehow this property appears unaffected: https://wcrz.com/the-worlds-largest-log-cabin-is-in-michigan...People love to point out rising levels but discount levels when they drop.

This year, between tenants, I will be replacing the carpet with vinyl flooring, updating the bathroom vanity/lighting/mirror, and some other small updates such as changing out light fixtures, and faucets, and switching the old blinds from fresh curtains.

I think a strategy that would serve me well is one where I buy a 2 (or 3) bedroom house with 1.5+ bathrooms.

I do discount useful life and increase costs to be on safe side. 

I would try to get him to take possession earlier for a discount so at least you have utilities and etc out of your name and some money coming in earlier even if he doesn't fully move in earlier.

The bathroom is right next to the kitchen.