I can listen to books and educate myself on whatever I want while at the gym, in the car, etc.There are a wide array books available and a few I think may benefit you to start with are...Buy, Rehab, Rent, Refinance, Repeat - The BRRRR Rental Property Investment Strategy Made SimpleFLIP - How to Find, Fix, and Sell Houses for ProfitThe Ultimate Guide to Wholesaling Real EstateBigger Pockets has become one of my best resources.

Market wide data and trends I think are useful, but don't bank on the expected revenue figures for given zip codes. 

The guest had brought additional guests than they listed on the reservation, doesn't respond to my messages/concerns, left my front door wide open when they left. 

@Dennis Tierney It can be a wide range depending on the property type but that's in the ballpark. 

This can vary widely.

I generally am focusing my search on a specific market, specific location, or maybe a major retail corridor, so I'm not casting a very wide geographical net. 

Terms can vary widely in this category from annual interest rates, prepayment penalties, income calculation, DSCR ratio, maximum loan to value, minimum and maximum loan size, amortization period, and requirements to escrow taxes and insurance. 

I sometimes set him up with my loan clients.Since I set up loans every week, and deal with a wide variety of sources for the loans, I see what the lenders do to reduce risk.

And, they have a wide variety of structures and risk/reward ratios for different types of investors (from no leverage to leverage, different sub asset classes, different geographies, etc).

Chicago is indeed a vibrant market with many opportunities, especially in the multifamily sector.Here are some tips and considerations as you prepare for your move and property purchase in Chicago:Research Neighborhoods: Chicago is a varied city with a wide range of neighborhoods, each with special qualities and investment opportunities of its own.