Due to the age of the house, figure in a lot of $$$ for capital expenditures. 

I do not know how much capital I would have, though I would like to acquire at least $10,000-$15,000 in cash for my FHA 203k loan, as well as having an emergency fund for minor repairs, capital expenditures, vacancy, and so on.

Cash flow from each property should be at least 100 per door after accounting for all expenses, and at least 15% cash on cash return(Capital expenditure, property management, vancancy, etc…) Time frame for each property ideally would be forever, but realistically every 3 years we should evaluate our strategy with each of our assets.With Multi Famlies, we will need to fill in the gaps of knowledge with what the numbers look like in the region.

You can reduce recurring costs and grow your business nationally and not have to learn every single new market by leveraging inspectors, appraisers and Realtors, they'd only be paid on a transactional basis so capital expenditures would be directly tied to how much revenue you generate. 

Additionally not inspecting or accounting for bigger ticket expenditures like (HVAC, flooring, roof, plumbing, electrical, foundation, and appliances) will reduce your profits the fastest.

@Matt Peebles capital expenditures.

Don't forget your capital expenditures.

@Brandon Turner has recently been saying a lot about the 80/20 rule in effort expenditure: 20% of your work produces 80% of the value.

Look at your other expenditures and debts to see if you can pare those down while you still have the full time income.  

@Michael Randle CapEx (Capital Expenditures) are those costs which, when incurred, will be amortized over a fixed period of years (Roof, new electrical, plumbing, windows), where as repairs, as @David Faulkner pointed out, are minor and are expended in the year they occurred (leaky faucet, new garbage disposal, clogged sink/toilet, one broken window, etc).