Short answer. Yes. If you left your property with someone who agreed to keep it for free, you must repay whatever he spent to preserve it. The Civil Code puts that cost on you, the owner, because the keeper is doing you a favour and was never meant to be left out of pocket.
What the law says
If the deposit is gratuitous, the depositor is obliged to reimburse the depositary for the expenses he may have incurred for the preservation of the thing deposited.
Civil Code, Article 1992 — Reimbursement of Preservation Expenses. Read the full provision →
What the law puts on the owner
Article 1992 of the Civil Code deals with safekeeping done for free — you handed something over and no fee was agreed. The Code says that if the deposit is gratuitous, the depositor is obliged to reimburse the depositary for the expenses he may have incurred for the preservation of the thing deposited. The depositor is the owner who left the thing; the depositary is the person who agreed to keep it. Because the keeper earns nothing from the arrangement, the law does not let a favour quietly turn into a bill he has to carry himself.
Preservation means keeping it as it was
The spending has to be for preservation — what it takes to keep the thing in the condition it was received in. Feed for an animal, storage that stops papers from being ruined by damp, a repair without which the item would deteriorate: these are the kinds of cost the article contemplates. Money spent to make the thing better, larger or more valuable is a different matter, and this provision does not oblige you to fund it. A keeper who wants to go beyond preservation should ask the owner first, because the article gives him no automatic claim for improvements.
What the article does not decide
This is a narrow rule. It settles who bears preservation costs in a free safekeeping and nothing more. It does not turn the arrangement into a paid one, and it does not entitle the keeper to a fee for his trouble. It says nothing about what happens if the thing is damaged or lost, which is governed by separate provisions on the keeper's care and liability. Nor does it let the keeper use the thing to recover his outlay. Where a fee was in fact agreed, the parties' own terms on expenses govern, and this article is not the starting point.
Practical points for both sides
Record the arrangement even if only in a message thread: most fights here are about whether the safekeeping was really free and whether the spending was really necessary. A keeper should tell the owner before incurring anything substantial and should keep receipts. An owner who is told and stays silent will struggle later to argue that the cost was unwanted. A refusal to reimburse is pursued as an ordinary civil claim for a sum of money, and claims do not stay open indefinitely, so raise it promptly rather than years afterwards. This is general legal information, not advice on your own facts.