One thing to note when getting conventional mortgages and spouses.There is a 10 limit per person for conventional financing.You can either do 10 conventional in each person's name which would be 20 mortgages for 2 people or if you do the mortgages jointly, will only allow 10 in total.My thoughts are not to own joint assets until you are both married. 

I have not done it personally but have some insight, maybe my reply may boost your post to someone with more experience in it. 

As far as the business card is concerned, to me personally I think having both things on one business card is acceptable .  

Or, OP can sinply avoid doing business with anyone who does Sub2 as they're likely a criminal or a con artist.  

We have helped several businesses open up using a Tiny Home to fit their business needs along with the City of St Louis with their homeless project.

Is there a point of contact person/business that handles all home investor concerns (general contractor, engineer, etc.)

Personally never heard of this scheme or way to set up transactions. 

The FFE and other assets of the business cannot be 1031d anyway. 

That is just my personal opinion

However, I'm short on cash (will be putting $20k of my personal money into this)  and I am exploring creative ways to source funds for the project.I’ve been quoted for a $100K HELOC on my primary residence with a 30/1m ARM at a 13.25% rate and APR, with an interest-only monthly payment of $1,016 and $3,825 in points.