As for item #3, I have quite a few properties including our ex home.  

Because you stated this will be your first purchase I can show you a few items below to expect.

In my STRs (beach market), couches are the most replaced furniture item, being updated every few years.  

@Lisa Beard In order to factor this into the deal, you would include a line item for property management in your deal analysis / underwriting.

For a savvy buyer a mini-split will have higher value than the traditional system.

You have to get a good deal of course and this financing is way easier than traditional financing.

The item that @Wes Evans noted is under "License Requirements" and I am pretty sure it is stating that if the ADU is constructed under the "Owner/Builder exemption" (no licensed contractor used) then the ADU cannot be rented out.

I would wait, you could put that money into bigger items to get a bigger and better value add.

Let's say you bought five $200K houses using traditional financing and put 25% down. 

The carpet is in terrible shape and the kitchen countertops (white laminate) need to be replaced as they are damaged from the tenants placing hot items directly on the counter.