Are SDIRA proceeds tax-free when I am already in retirement?

[Jeff Anderson]

I am 71 years old and retired. I am taking my social security benefits but I also have savings in a 401k, and a Roth IRA. I've been approached by a local real estate investor to become his "private lender" on fix and flips he does. He has suggested that to defer taxes I first transfer $150k from my current Roth IRA account into a new Self-Directed Roth IRA custodial account that I will open. Then, lend him the money for purchases and rehabs. The lender will be the SDIRA account. These are mostly 6-month interest-only loans with 2 points up paid at closing. So, theoretically, a six-month loan of $100k could net $2k in points and another $6k in interest payments totaling $8k in fees and interest.

Here are my questions:

1.  Are these proceeds (fees and interest payments) taxable?  It would seem that they are not since the Roth SDIRA is the lender.  

2. Is there any waiting period until I can use these proceeds, not to lend again, but to spend personally? I seem to recall there was some kind of 5-year period with a Roth IRA before it could be used.

Any insight you all have would be most appreciated!

Thanks.