Is it Mutar to ask a Rav a monetary Shaila on Shabbos (assuming your are not merely asking for the sake of Torah, but the Shaila is actually relevant practically)?
The Aruch Laner says that questions about practical monetary matters may not be judged on Yom Tov. There is reason to assume that that Shabbos would have the identical halacha.
He says this in the course of explaining a fascinating gemara in Sukkah 31a:
ההיא סבתא דאתאי לקמיה דרב נחמן אמרה ליה ריש גלותא וכולהו רבנן דבי ריש גלותא בסוכה גזולה הוו יתבי צווחה ולא אשגח בה רב נחמן אמרה ליה איתתא דהוה ליה לאבוהא תלת מאה ותמני סרי עבדי צווחא קמייכו ולא אשגחיתו בה אמר להו רב נחמן פעיתא היא דא ואין לה אלא דמי עצים בלבד
The Gemara relates: There was a certain old woman who came before Rav Naḥman. She said to him: The Exilarch and all the Sages in his house have been sitting in a stolen sukka. She claimed that the Exilarch’s servants stole her wood and used it to build the sukka. She screamed, but Rav Naḥman did not pay attention to her. She said to him: A woman whose father, Abraham, our forefather, had three hundred and eighteen slaves screams before you, and you do not pay attention to her? Rav Naḥman said to the Sages: This woman is a screamer, and she has rights only to the monetary value of the wood. However, the sukka itself was already acquired by the Exilarch.
According to the Aruch Laner's rendering, Rav Nachman could not tell her the halacha, since monetary matters may not be judged on Yom Tov, and he therefore ignored her. However, once she began disrespecting the Exilarch, he he taught the ruling to his students as a (theoretical) piece of Torah and allowed her to overhear. This subterfuge was only allowed since the dignity of the Exilarch was at stake.