I second YNAB, but as you said, it requires diligent tracking especially for those of us living outside the US and can't hook their bank account into it.

I happen to love the diligent tracking, though, and it's just part of my daily routine. Every time my wife or I charge a card or the money from the ATM, we log it in YNAB. Then every day I open my banking app and reconcile the charges with what we've input into YNAB. Sometimes we forget to log something, or mis-log something, or there are surprise charges to be dealt with.

Now that I'm in the habit, it takes a total of 10 minutes a day.