This is because the Schedule E is obtained independently, and few people would inflate their rental income in that form (and pay more taxes than they should).  

They go quiet when you ask how much money they've earned, how many deals they've done, when they reached financial independence, etc.

I currently work in the energy sector, but my ultimate goal is to become financially independent through real estate.

Greetings, I am a Real Estate Broker based in Washington State, with extensive experience in residential real estate and recent involvement in commercial properties. I am currently pursuing a Master's in Real Estate D...

You wouldnt be able to sell them independently from the main home. 

@Alec Jacobs We typically m aside the windows and buy our own and usually get a quote based on the measurements from both the box stores and an independent glass company.

IMHO the cash flow gives you financial freedom/independence (at least it used to with lower interest rates.), the appreciation makes you wealthy/rich. 

Rental income also sometimes has seasoning requirements before a lender wants to count it towards covering the debt you incurred.You don't mention how much income you will need to be financially independent.  

Example: "I want to build financial independence through real estate investing.

You can learn to do this independently or get a rockstar REALTOR to lead the way.