This is why this method is so powerful.  

I want this to be acceptable long term if I keep this method of financing. 

What are the best sources or methods you use to accurately set rental rates in your area?

Used houses in the area sell anywhere from $75-125 a square foot.These are long term rentals that I do not plan to sell.I am reading the Rental Property Investing book and implementing the method that focuses on cash flow and that strategy states you need to have $300 cash flow per month, per property.

Are there any methods you want to stick with?

There are also people who swear by one method or another.   

(G) Acceptable forms of payment of Rent (including Additional Rent) are ___ personal check, ___ cashier’s check, ___ bank check, ___ money order, and ___ the following online/ACH payment methods ____________________.

Find Brandon's videos on YouTube for the "four square" method of analyzing homes and practice.

Many opt for other investing methods in their SDIRA like private lending, crypto, private equity...anything except collectibles and life insurance.Note that a Solo 401k is exempt from UBIT on leveraged real estate so if you have self employment activity and no full time employees save for you and your spouse you should consider the Solo K as an option. 

If you are open to non-traditional methods of financing, you could use a debt service loan to bypass that requirement.