Keep clear records of money coming in and out.

or is it better to use a private money lender as well?

Personally, believe other people's money should be protected before my money. 

Properties have to be purchased in cash the day of auction, so besides raising private money from friends and family, are there any private money lenders that will lend to me using this strategy?

I’m interested in using private money to get started and continue using the BRRRR method as I love value add and I’m able to do a lot of the work myself.

My property manager recommends i notify the FBI but I'll be honest, I really just want my money.

If I invest that money into a rental property that breaks even, wouldn't I actually be cashflow negative $150 per month now that I'm not getting that interest from the HYSA anymore?

I also haven't ever had a CPA who demanded money upfront.

Hi Michael,So there's negatively, neutrally, and positively leveraged debt.You don't want negatively leveraged debt because you need to bring money to the table each month to pay for the bill.Positively leveraged debt throws off cash each month.

I know personal letters would take more time and cost more money, but I would rather send out less of higher quality then more at lower quality.Having said all of that I would recommend that you tell everyone you interact with that you are a real estate investor and tell them what kind of properties you buy.