They could have allocated 50-50 on the down payment division. 

Just choose an allocation method and stick with it (# of bedrooms, # of bathrooms, # of tenants or unit sq ft). 

The investment in the Qualified Opportunity Fund must be an equity interest (including preferred stock and special partnership allocation), but not debt.4.

One of the other business owners sits on the board for budgeting and allocation.

Landlord's decisions to go with a broker or to handle the leasing in-house is often a function of how much time you have to allocate towards leasing it yourself.

@Rob Brown Your asset allocation should be determined by your personal financial situation.

I can have my single family paid off in 8 years if I start rolling that money back into it, and if I do the same to my 4plex I can have it completely paid in 8 years after that if I commit those funds I budget every month to live on my employment income - what I don't know is if I should allocate my passive income back into my existing investments to maximize long term cash flow, or focus on buying new properties.

Thoughts on how to determine a just allocation in this situation?

A water heater or furnace in a $690/month rental would cost you the same as a water heater or furnace in a $1,300/month rental, yet the amount allocated for reserves using percentages will be significantly different. 

Do you also allocate a signing fee for new tenants with annual lease etc?