I am based out of Bolingbrook but work in Chicago and Oak Brook frequently.

For 2017, those rates are: $0 - $2,500 = 15% of taxable income$2,501 - $5,900 = $375 + 25% of the amount over $2500$5,901 - $9,050 = $1,225 + 28% of the amount over $5,900$9,051 - $12,300 = $2,107 + 33% of the amount over $9,050$12,300 + = $3,179.50 + 39.6% of the amount over $12,300With rentals, you can frequently structure them so that, in the beginning when the interest paid on the loan is high, there is no profit (due to the depreciation deduction).  

So you may be approved for lets say hypothetically $50K loan at a 3.99% APR but in just 5yrs depending how frequently the fed raises rates you could be looking at 6% or more by that time.

Check the filters (you can usually find the full box you left in the closet for the tenant on the day they moved in; frequently dusty and totally untouched way back in the closet). 

However I'm wondering what other expenses have come up, perhaps on a yearly basis (or even less frequently) that I should be considering in my calculations?

First, understand that agents get approached on a frequent basis by potential new investors that have unrealistic expectations or don’t follow through.

I do frequent the Black Diamonds meetings, there's a meeting coming up next Tuesday June 20th let me know if you can make it and maybe we can have a drink.

As an appraiser, I frequently find myself in a tough situation - I believe the value of a property is there (contract price) but the comps and market data show that it isn't.

One of the nice features is that you can define locations like addresses where you have properties, the usual stores or services centers that you frequent, etc.

If you move out in a few years to house hack another property, you'll still have those benefits and they'll definitely help the first property toward cash flowing better.The question of "bigger down payment on fewer properties, or lower down payment on more properties" comes up frequently on Bigger Pockets so I'd recommend searching for similar posts and seeing what comes up.In general, for newer investors my recommendation is that because "you don't know what you don't know" (i.e., this is mostly all new), that you put a larger down payment on one/fewer properties to give yourself a safe buffer for learning, for the market to turn against you, for expenses you didn't anticipate, etc.