Broker and or Investor : Industrial/Office vs. Multifamily

[Josh Reed]

My goal of becoming a broker is two fold:  1) Build a career with high earning potential   2) Use that income paired with the knowledge I would gain to invest. 

I understand  commercial brokers are not always allowed to invest within the markets they work.  My question is this. 

If you were to spend the next 10 years of your life sacrificing lots in order to gain knowledge of particular industry (Industrial or Multifamily) which would you rather know when all is said and done and you were to try and retire with this knowledge. 

Industrial or Multifamily 

Which would allow a higher earning potential as a broker?  For example:

If you could not invest in the field you were brokering, which situation would you choose

Broker of Multifamily and Investor in Industrial

Broker of Industrial and Investor of Multifamily 

I would greatly appreciate any thoughts and insights.

Thanks.