In order to get a certain solar loan 3 or 4 years ago, my wife and I both had to open accounts with a particular credit union. We paid off that loan about 6 months ago

About 2 months ago, my wife got a notice in the mail from the Credit Union, showing that her account balance was now at negative 5 cents. Apparently a recent account management fee of $5 had taken her negative. I believe that that just automatically closed the account. They weren't trying to collect the nickel.

But we didn't realize that my wife's account was getting a $5 a month management fee applied to it. Mine wasn't. I THINK because mine had a higher balance to open the account.

So shady practice by the bank to not inform us in any way that they were taking $5 a month from that account?

Or stupid us for not A) being aware of whatever the minimum balance was to avoid fees and B) not checking on the account on occasion and noticing the fees?

Note that even though they 'stole' $150 from us, the loan and solar was still worth it, but it does lessen the NPV calculation.