The landlords that I know that get tons of maintenance calls are the ones that don't property maintain their units.

It had 2 kitchens a huge living room, a pool table room, 5 bedroom & 4 baths.They are interesting pieces of history that require some very unique knowledge to maintain, but people love them.

The biggest drawbacks to multi-family is that often you have to pay the water (single water meter for the building and thus no way to bill back to tenants as you can with single family houses), you typically have to maintain the yard, and your average tenancy duration is likely to be slightly lower (people who prefer to live in single family houses move slightly less than people who live in apartments/units in multi-family properties, especially once you are in areas better than 'C' quality).

While these are very good and strategic thoughts on your end, it is imperative that you maintain within the guidelines of the city's regulations and adhere to their codes for the safely of the public and for you as the owner or landlord. 

I build and maintain Koi ponds, Waterfalls, and offer Lake management services as well.

Other than that, home has NOT been maintained and is in very poor condition.

The boilers are 50 years old, and I knew zilch about maintaining them, so I appreciated this. 

I like short term better myself because I don't have to deal with evictions, the guests pay in full before their stay so no chasing rent, and we get to get into the properties after each guest stay to make sure it's well maintained and issues fixed immediately.

However you wanna phrase it, you wouldn't be able to maintain profitability running a property management business with nothing more than a 10% monthly PM fee.

In doing so they would maintain their ownership in the property as being "investment" (and thus tax deferred) while it would still be considered primary residence for myself and thus qualifying for the home gain exclusion per section 121?