If you are in the 30% tax bracket, that is approximately a negative 25% ROI for the plan principal that you borrowed.And, you will be taxed again when you eventually withdrawal this capital from the 401k in retirement.So, the benefits of borrowing from the plan in order to fund an outside deal need to be well worth it.In my opinion, too many folks look at this as "easy money" and promote the 401k loan as a great way to get started in real estate.  

I get added to newsletter lists all the time but most don't add any value to my business...they only promote the sender's business. 

Think about that.I don't consider myself a Detroit Promoter.

This may seem difficult, but I'm sure we can pull it off and will promote creativity and education in the process.  

and maybe have an  advice how to promote it in a better way?

Sometimes it just higher ownership (sometimes known as a promote) and sometimes it is an actual fee.

I'm not promoting that or saying I would do it but it would be interesting to see if there are actually any checks and balances on this aspect of the loan.

So if you ever do a rent promotion like "First month's rent for $1" then your deposits are only $1 each.  

Typically, until you reach a certain hurdle, you will not be collecting any sort of equity promote.

Its why the mods are so tough on promoting..If I was you I would take others advice and save your money and DO NOT buy a single rental in the US... not worth the time energy or Risk..