Solo 401K/ IRA and Tax concerns under my LLC

[Account Closed]

Hello, very new to this forum and this topic.  I am trying to put together the following information and would be grateful for any thoughts you all may have.

1.  I would like to take one of my current employer 401K's and make that self directed.  Once that is accomplished I would like to use that money to fund either hard money loans or purchase rental property.  Question:  I am assuming that either the interest from the loan or the rental income would be tax deferred?  Is that correct?

2.  I am also thinking about doing this with after tax money but would like to shelter as much of the loan interest and / or rental income from taxes.  I read some on this topic but I am getting confused on the terms Active vs. Passive income.  It appears Passive income is bad since it appears on my 1040 as regular income which means I cannot subtract my expenses first from this amount?  Is that correct?

3. I read in another blog that getting a mortgage for a home owned by a LLC is difficult? Why is that?