Obviously, this can depend on how you define success but for a newbie, what should their focus be?

Since the map for you is much more wide open, instead of recommending an area for you to search I would suggest having a conversation with a realtor or a few to define what you are looking for in an area.

But first it takes clarifying that end vision, then defining the strategy.Hope that helps!

They can vary between B and C class neighborhoods however, so you need to define your criteria and know the neighborhoods well or work with someone you trust that does.

This will define legal bedrooms.

You cannot accelerate the depreciation of your entire property to a 5 year schedule, however there are many components of that property that can be.

The IRS does not care if you buy a house, improve it and sell it or buy computer components and assemble them into a PC. 

Your goals might be different -- define the goal and then see if the property meets that criteria.You might want to consider running numbers in the BiggerPockets calculator, but they have a fantastic rule of thumb to help quickly gauge cash flow and COC return -- take total monthly rent x 50% ($1,125 per month), add your PITI (lets call it $1,175 per month - $650 mortgage, $425 taxes, $100 insurance), add up those two numbers (1125+1175 = $2300 per month), and subtract from your monthly rent of $2,250...based on that model, you'd be looking at a $50 cash flow loss per month.

If you want that first one to still have an investment component, then house hack it either renting out the rooms or finding a home with a basement apartment. 

Getting a job is a defined 40 hours a week (or 50+ in my case), very known time requirement.