My father set up a solo 401k in which he owns a paid for duplex.

My father had a broker license when I graduated and mostly worked on commercial deals. 

The type of investments your father will be making are going to determine the best tool for the job.Self Directed IRA Custodians will typically have the word Trust in their name. 

A father and son duo made a business out of handing foreclosure notices to homeowners just past the housing market collapse.

I'm in a farm partnership with my father in law(fil) and my brother in law (bil). 

I only suggest that because my Father and Uncle are both doctors and were very happy they made the decision to build years ago. 

@Sean McGrattanIf you are looking for a reference on commercial real estate closer to home, you will want to roll your change and pickup a copy of "Commercial Real Estate Investing in Canada" by @Claude Boiron and his father Pierre.

(House was built in 1920, I would assume there is lead based paint and my father seems to think the siding on the house is definitely asbestos-based)12.

My father paid his property off and just pays taxes and insurance. 

My wife lost her father and step mother within about a year of each other.You may want to talk with a CPA about any tax obligations that may result from your inheritance.