I believe I put about 60k into the rehab which included adding a fifth bedroom to the basement.

Yes I often hear PPR and DLP in the same breath as they both seem to offer solid income with fairly low risk.

But, like everything in lending, when you "risk layer" the rate/terms are usually a little worse.

Many investors if they make a mistake can recover as long as they took risk proportional to their tolerance and income.

there is a risk that you will die or be involved in an accident every time you drive a car. 

You can consider and explore other low- and no-money-down strategies, such as seller financing and sub-to, but these come with risks and can be pretty nuanced.

Risks/rewards, benefits/pitfalls of hard money to me...what are they?  

Using simple numbers, assume I want to purchase a $100,000 property using crypto as collateral:- I pay the closing costs with cash- I put down 10% down payment with cash ($10,000) - I utilize a crypto mortgage for the remaining 90% ($90,000) This way, I still keep my crypto and I have a property, both of which may accrue in value over the long-term.

A refinance into an LLC avoids this risk but typically requires a commercial loan with higher rates and stricter terms.If asset protection is the main goal, umbrella insurance may suffice without disrupting financing.

Based on your description, it sounds like you would violate the self-dealing rule and could put your SDIRA at risk.