I will be paying about 45k per door for these units and they will be paying me $3000/yr each or $18,000.

My early goals were to buy so many houses at $200 a door.  

Scale and iron build up will excellerate wear and tear on anything that water touches including dishwashers, water heaters shower doors etc.  

Windows are new, also might need a new front door.  

@Mary Jo There’s no difference between occupying your own and renting the one right next door.

I would bet you’ll be lucky to get 100 bucks a door realistically when all the corrections are made and it’s running .

If you really are going to get rents closer to 30k, you'll be at roughly 8k/yr or roughly $100/door per month. 

And some unexpected costs (e.g. had to replace a lot of doors I didn't think about).

If we don't hire a property management company to manage our 3 door rental, but then we need to evict someone, are there property management companies that will just do this portion for a fee? 

Next door to that there was another duplex I have been eyeing and lusting after for six years.