Are normal bank transfers not a thing in the USA?
There's a nonzero chance you will hit some kind of risk/fraud system based on amount too.
Wire is much better but frequently $50-100 per transaction as a fee.
Just for comparison, in Germany, bank transfers are free and take 1-2 days, for a fee or free (depending on the bank) you can do instant transfers taking seconds.
(If you don't explicitly have overdrafting off, so that it would just fail your transaction instead of letting it go through. The default setting may have changed in the last decade due to law but I remember these scenarios vividly)
$0 balance
+$20
-$1
-$1
-$1
Within a day or two of each other won't necessarily be positive $17 balance.
It could easily become:
$0 balance
-$1 (overdraft fee $40)
-$1 (overdraft fee $40)
-$1 (overdraft fee $40)
+$20
= negative $103 balance
Banks make a lot of money doing this to poor people. The financial class is full of super-predatory behavior.
Gaining access to a credit union was one of the best things that ever happened to me.