Best thing to do - make an appointment at Boston P+Z, sit down with a Planner for guidance and educating yourself first hand.

It takes the same amount of time to source and manage a 25% down payment rental as a 30% one...there is no difference between the two.Maybe you are asking if it's okay to put more money down to achieve your target cash flow. 

@Brian Gerlach is right, through education you are already ahead of the curve.House Hacking is an excellent strategy and we have helped multiple clients achieve that. 

You will have first hand knowledge of the necessary expenses to run this type of property, the leasing and turn over process as well as marketing.

If you can not achieve that level of financial control you will never be able to invest.

@Pat JacksonWhat others have said in regards to interest rate on the note, value of home, payment history (highly recommend using a servicer and not servicing yourself), LTV at time of sale to note investor, records of payment history, market conditions and a number of other factors are all great points.I would say that most performing Note investors are looking to achieve a 12-15% yield. 

But hey... mediocrity is your goal, who can stop you from achieving it.  

It felt like a low-risk buy (since we could easily cover the mortgage even without renters), but since the unit was almost always filled I saw the full power of REI firsthand. 

As a non-experienced first-time investor, I am not sure how else to experience rehabbing first hand. 

I strive for about that return year 1 of a single purchase and mostly have achieved it.My view is the OP either has to increase his cash flow significantly ($400/unit could work) or invest in a locale with historical appreciation that is above the inflation rate to obtain a return that is likely to be impactful to his life.