Other places might seem like they would be ok and they might for a little while but for a bit more money you can pick up an SFR which I think would make much more sense.

Go to biggerpockets.com/books and pick any of those books, especially the book on rentals by Brandon Turner.

Well we picked the wrong stinking hardwood.

When I graduated college my father was into comm'l real estate and was a licensed broker and he taught me a little bit.The main thing to do is to educate yourself and once you decide what you want to do, focus on that style you pick out 1 or 2 areas and make sure you know them well. 

I'm doing a HELOC now to pick up a property in Dorchester, however I'm pursuing a BRRRR strategy with the intent to paying back the entirety of the line of credit after the refinance.

All you need is lots of money and the knowledge to pick and train the right PM.Oren gave you some very valuable information, I would seriously consider following his advice.To answer your specific question about garbage removal you would need 2, 2cu.Yd.

Since a renter cannot go without food, most will not go without medicine, they cannot go without transportation and most do not want their kids to go without these either, they have to pick and choose often which bills to pay and how much.Rent is usually the very first thing to get behind in emergencies.   

You can pick up a small thermometer at a big box store that shows humidity for like $10.    

I'm in agreement with finding the people in your area that are doing what you want to do and pick their brain as much as you can.

First off, pick a state.