Deal analysis- Chicagoland area

[Account Closed]

Hello everyone, 

I'm new to the forums and I recently started reading more about real estate. I have seen a few properties that I like, and I hope someone could provide some advice analyzing this deal. 

This is the property I'm planning on buying. 

http://www.realtor.com/realestateandhomes-detail/3...

This property is located in Aurora,IL, it's a suburb 40 minutes away from Chicago. Here are my cashflow estimates:

317 Oak Ave Aurora,IL
Rent/mo/unit	$2,600
Gross Potential Rent	$31,200
Occupancy Rate	0.9
Less Vacancy Adj	3,120
Other Revenue	0
Net Rental Rev	$28,080

Management Fees

2,808

Property price	100,000
Loan	80,000
Mtge Payment	430
SQ Feet	7405

I'm estimating an NOI of $25,272. I'm not an expert, so if I'm missing something (perhaps I should add more items under expenses) please let me know.

The net cash flow of the property is 15,324.00

Net Operating Income	$25,272
mortgage	5148
taxes	3000
insurance Expense	1,800
Net Cash flow	15,324

My main concern I have is underestimating expenses and overestimating rent. Does anyone has any tips on estimating rents for an area? So far I've gone on craigslist and check comparable properties. The vacancy rates are also estimates, but I'm hoping a property management company can give me a more accurate estimate. 

I really haven't looked at the property yet. What are some of the most common repairs you do on a property after buying it? 

I'd really appreciate any piece of advice as this would be my first time buying a property.