It is probably the most critical component of investing in multifamily.

Per https://www.ci.richmond.ca.us/DocumentCenter/View/61839/MNOI...Fair return defined Kenneth Barr method (MNOI) which the Courts have agreed with:“as the price controls are not confiscatory; i.e, they do not deprive investorsof a fair return on their investment.”  

@Zachary Hadjah,Let's define some terms to better answer your question. 1. 

Many alternative lenders have internal guidelines that prevent against lending on assets with any commercial components.

https://michiganchronicle.com/2024/01/03/major-developments-that-will-define-detroit-in-2024/Hit me up if you'd like to know more.

I would only do it where the regulations are well defined.

@Zac Kucharek  I will focus on the asset protection component of your post since it appears to be the primary objective.  

When lenders use the term "Rural" it can be very frustrating for a borrower because the term is rarely clearly defined.

"Better" can be defined in terms of risk and return.Risk - You told us nothing about the investment nor GP, so it's impossible for us to really comment beyond lower risk might be better.

That said, Solo 401(k) with Roth component can be powerful and does open up the discussion with your CPA or tax pro about paying yourself more (within reason), in order to make higher contributions.