Yep, in the enterprise and commercial space it can make sense.My mgt co s-corp rents space from a multi-use building owned by one of my commercial LLCs.I may not ask for SBA relief, but its an option.I don't see using it in a househack primary situation, though I have rented my house out for 13 days a year for a few years now.

I am a residential multi-family investor looking to expand into the commercial real estate space. 

You need to become an expert in the space or partner with someone who is to fast track yiyr success. 

Plan is to continue to monitor the 3/4 unit space in my area and see what happens.

I use: Tenant acknowledges common area amenities such as pool, patio, lawn, and entertainment space outside the unit are maintained by the HOA and are outside the control of landlord and as such, landlord cannot guarantee their continued availability.

If you own office space that is going to difficult as companies who downplayed remote employees are probably finding out that you don't have to put everyone in cubicles every day. 

The quick math tells you you have 6000 ft per floor so 60x100 works for 18 units and 8000 ft per floor for 24 units or 80x100 so your actual dimension will depend on site constraints.

Size constraints, flooding potential, topography, etc.

Either way way, it detracts from the aesthetics of your space. 

I expect the group to be closely monitored for these types of behavior, as I don't want them in here since this is to be a safe space to learn from each other.