Checking Account/Money Market Fund

I have all of my income sources directly deposit money into my checking account the I have had with USAA federal savings bank for many years. From this account, I pay all of my bills (most via ACH) also.  
I reconcile my checking account monthly and transfer any amount over $1000 to my PMMF @ Vanguard. If the balance is less that $1000, which it seldom is, I move money from the PMMF to the checking account.
 
This is my simple way of controlling all income and expenses and I have used it successfully for over 20 years without a hitch.