I think is a really powerful strategy to grow your portfolio fast and to get all the benefits of owning real estate. 

The biggest benefit of real estate -- house hacking or otherwise -- is time in market, so my advice is to not overthink it. 

I m still occupying and paying rent and utilities and that that was not a reasonable repair during my tenancy that would benefit me so they would probably need to to come back April 1st.  

There are big benefits in holding a property rather than buying a new one such as that the property taxes will be lower due to not being reassessed as they are on sale.

Will he still have to pay capital gains if he sells?

The benefits of buying a primary or first time homebuyers is that rates are typically lower than investments because the governments incentives to buy houses even for 2-4units now as min as 5%.On the other hand, you can repeat the process every year through house hacking and rent out your current primary house by converting it as a rental and acquire another property.

I could not see an obvious benefit to House hacking this property as opposed to renting both units out?

You have more potential to gain equity through appreciation with multiple homes than one commercial property.

I really enjoy the podcasts and I hope to gain more knowledge from experienced investors here on this platform. 

The BiggerPockets podcast and resources, including books by J Scott, are excellent tools to learn from seasoned investors and gain valuable insights.Utilize BiggerPockets Resources: Make use of the podcast, articles, webinars, forums, and other resources available on BiggerPockets.