It is possible to be successful in either - it depends on your skillset, your goals, your time and many other factors. 

@Rud SevCap rates in NNN deals are influenced by factors like tenant quality, lease terms, location, and lease structure.

Now if you want to buy and live there forever or you want a specific location or lifestyle or the amenities, might be something to consider, but not for investment....they're for living.Your best option right now depending on your income, is probably to buy at least 4bed house or 5 bedroom if you can make it work financially and rent bedrooms. 

There is no differential factor number, however, it will change if you are buying tenant occupied, if they are are going to be vacant at closing, if they are going to stay the full lease or you have to pay cash for keys.

Several things to consider: 1) One of the main purposes of segmenting your assets into separate LLC's is so that your personal net worth or equity in other business ventures or properties isn't exposed, so unless you have a high net worth or a lot of equity in a property, it might not be worth bothering going the separate LLC route, especially when it restricts your financing of the property.  2) Most any commercial financing you get from a local bank for a small property is going to have recourse anyhow and require that you sign a personal guarantee, so you're still personally on the hook to the bank even in the case of a commercial loan.  3) If you're a newer investor and buying a deal that's tight on cash flow, or if you don't have a ton of cash sitting in the bank already, your greatest risk factor as an investor is your investment failing economically due to poor financing terms or not operating the investment properly, not because you get sued. 

This amount will be a direct cost of refinancing that you'll need to factor into your overall analysis.3.

Also, I’m not into tax evasion necessarily but she’s owned the place forever and has minimal taxes.

When house-hacking with 5% down, returns on cash invested could be huge when you factor in the appreciation gains.

I’m not trying to rain on anything here but the reality is that measuring Btus delivered to individual units via airflow is by its very nature imprecise - if you want to know why, read on...The size and length of the ductwork is but one factor ( of many) that will yield energy losses while that warm air is being moved to your units.

Quote from @Sharon McCants: Consider all the factors before making a decision.