Marketing, overhead, operations, what have you, this could be baked into your rate, furthermore, your lender is most likely not even providing the capital to fund the loan nor will they service it unless they are a credit union or the type of lender that does service it.

The max Uncle Sam allows is 50k if you haven't taken a TSP loan in the last year.I've seen both good and bad experiences with this but at the end of the day it's no different from any other type of loan, you are just your own bank in a sense.The downside or risk is that you lose your job, your property isn't cash flowing, are unable to pay back the loan, and your retirement account suffers since the loan essentially turns into a withdrawal.The upside or best case is you have the loan for less than a year, your BRRRR pays off the loan, and you pay yourself interest 5% interest.The opportunity cost is if the stock market goes up 20% and you were only paying yourself 5% interest you'll miss out on the excess returns. 

I’ve been doing this type of work for way too long, earning whatever number it is my “boss” thinks I’m worth, and I want a career change that gets me out of the rat race.I want to be around happy people (for the most part) doing something creative, that makes me happy, free and lucrative, one that allows me to be my own boss deciding how much money I make, and on my way to living an essential life with multiple streams of income that include me in Europe, writing stories in my free time.

Cisco,It really depends on the loan type.

@Jacob StraussenWhat type of policy and face amount? 

I am looking into purchasing a single family home ,and converting it into a duplex ,and a 2 car garage into a ADU what type of loan is recommended ?

What made you interested in investing in this type of deal?

I just typed "biggerpockets house hack Canada" into Google and there are a bunch of threads about it. 

Purchase price: $170,000 primary home 15yr fixed 2.75% 10yrs left on note What made you interested in investing in this type of deal?

So, if you are getting a DSCR style loan, those types of lenders won't have those types of restrictions.