It doesn’t matter what the exchange rate was. Clearly, he chose an Esrog that was far beyond what he needed to perform the mitzvah. Heck, it was far beyond what would even be considered a “nice Esrog.” He would have been much better off putting the rest of the money aside to be able to continue learning in Kollel until the regular payments started up again.
And I think it’s trying to tell us that you can never go wrong with spending extravagant amounts to beautify Hashem’s Mitzvos. Wouldn’t you agree?
Absolutely not. One has to learn to live within his means, even if it means he won’t get the nicest Esrog, the most beautiful menorah or the most beautiful k’sav in his tefillin. And, I doubt you’ll find too many rabannim who, given the situation in the film, would agree with what he did.
The Wolf