If I'm expecting a top rate of rent and the market for that unit at that rent is thin, will I have more vacancy or will I have to reduce rent?!?

Since you deposit all of your money into the account right away, the HELOC amount is reduced (and therefore less interest) for the time between when you get paid and have to take some of the money back out to pay your bills. 

In order to provide for as many participants as possible, Baltimore City Routinely REDUCES the Section 8 Voucher payments, from year to year. 

The viewpoint also under states the value of reducing tax burden NOW vs. later. 

You'll be able to acquire an asset with little money down, reduce your living expenses and learn a lot about real estate investing.Will you have a W2 income?

While this would require "house-hacking" and losing the rental income from one unit for a year, I have a high W-2 income that could compensate for the reduced cash flow in Year 1 of ownership which should make the banks happy. 

I had a feeling it was a scam to get the rent reduced for that month. 

If you increase your amortization to 40 you reduce your pay down and increase your interest rate.

But that person would have to be on the loan in order for the experience to count.I usually encourage partnering with an experienced investor for the first few deals in order to learn and reduce your risk by minimizing "newbie" mistakes. 

I think you can learn from this experience and reduce the likelyhood of it occurring again.