Seeing as how this would be my first time partnering up with someone, i would like to draw up some kind of agreement contract assuring the percentage i would be owed if he manages to successfully wholesale to one of his buyers.

Only a small percentage will ever respond - even if you have the right phone number for every one of them.My investor customers have purchased $40B+ in real estate, and my agent customers have likely listed a similar amount (harder to track so I don't know for sure).

The interest rate doesn't matter, as long as I'm getting at least $350-400...depending on how much (in dollars...not percentage) I put in as a Down Payment.

Believe the percentage is higher now, but the CC&R may not have to reflect that.

CMHA also requires the tenant's total monthly rental amount to fall within an acceptable percentage of their gross monthly earnings.

@Mike SolaIncome taxes by themselves usually won't flip ROI from negative to positive and vice-versa as tax liability is a percentage of taxable income and tax benefit is a percentage of tax loss. 

Since 2016, however, we've seen this jump to an annual growth percentage of 7.88%.

As long as she pays and the percentage/late fee is more than what you would have earned on the rent had you invested it for a couple of days extra each month, I would renew.

I'm not sure what your management team costs, from what I've seen most low rent places take a flat rate instead of a percentage. 

No, if your operation agreement states who owns what and in what percentage.