The caparra confirmatoria is set out in the Italian Civil Code and is not just an advance. If the person who paid it withdraws, the other party may keep it; if the person who received it withdraws, they may have to pay it back doubled. That is why the word written in the contract matters: a deposit (acconto) and a caparra have different consequences.
Couples marrying from abroad rarely know this distinction, so it is worth having it explained, perhaps with a translation of the contract. If you are unsure how the clause is worded, ask a professional before you sign. The guide to the contract with your florist gives the legal reference; the one on how to read a florist's quote explains how it differs from a deposit; the sample quotes show where it appears.
What to ask: whether the payment is an acconto or a caparra, and what happens if either side cancels.
