Rule reminder
The condizionale passato is used in very polite contexts: Avrei preferito... (I would have preferred...), Avrei voluto chiederle... (I would have liked to ask you...), and to soften criticism: Avrebbe potuto dirlo prima (He could have said it earlier).
Come cliente in un ristorante: '___ (potere) portarmi il menù, per favore?' (Very polite, past form)