I'm working with a company who owns a small, 19 unit, senior and low income apartment building.

BP has done such a great job of promoting SFR investing to the masses, that those masses have pushed up real estate prices to where it's now DIFFICULT to cashflow right away.Keep going, but understand you won't get rich in real estate overnight - it's a long-term wealth building strategy.For the short-term, recommend joining a few in-person investor meetings if possible, otherwise online ones.

Many banks wont touch deals that are sub 90% occupancy, so you could negotiate short term seller financing to help give you runway to make the building bankable for a refinance while you reposition it.

Just be prepared for potential vacancies.My advice is to build relationships with university housing offices.

Since you have a primary focus on house hacking, saving money, building equity in your current investment. 

In my 30 years doing this I’ve found that as long as you address each issue that comes up properly and do the repair needed to bring that part of the building up to current code then you will be fine.

I'm looking to build a Casita/poolhouse for use as a short term rental in Summerlin.

However, tenant insurance is typically intended to cover personal property and liability for the tenant, not the building itself.

The DCA has on file that the property is only a four unit building.

A personal liability policy "MAY" extend to one or two rentals but if you are planning on building a portfolio consider the commercial umbrella.Another thing to consider is that the courts frown on carry high personal liability but low business liability when trying to hide behind the vail.