Another question that arises is how to do this without piercing the corporate veil?

From a liability perspective, you should be consulting with an attorney (and CPA) to be sure any transfer you are doing is not "piercing the corporate veil" and opening you up to personal liability.But from a moving of money standpoint, you won't have any issues.  

To keep the DST from being pierced you MUST maintain compliance or the structure will collapse and all series would then be treated as one.

Meanwhile, if you don't operate that fancy structure correctly, you'll pierce your corporate veil and lose that limited liability. 

If so, you have a very low likelihood of being sued anyways, and even if you are sued, there are countless ways attorneys will try to pierce the corporate shield and come after you personally anyways.Will you be financing the properties?

Or they stick with what they are familiar with and try to fit everybody into one system (LLC / Land trust).Most asset protection planning is limited, especially in CA where courts have pierced the veil of LLCs set up for asset protection and pierced the veil.

In short, adding little bits of money at a time would (in retrospect) have a court consider the entity as an alter ego of yourself (and your partners) and subsequently "pierce the corporate veil". 

Set up an LLC in a state that makes piercing the veil difficult and then behave well!

- Upon having that LLC I know one shouldn’t mix business and personal expenses because of possibly piercing the veil.

Whether or not that effectively destroys any protection the LLC provided you (because you pierced the corporate veil) is a question for an attorney that knows your state laws.Personally, I just got a $2M umbrella from my personal residence.