The In-Depth Answer
No, it is not necessary to be in San Miguel for the closing. However, you will need to give someone a power of attorney (POA) so that they can sign on your behalf, in person, on the day of closing. These powers of attorney are usually drafted by one of the attorneys in the notary's office and, unless otherwise specified, allow the person with the power to also sign off on the distribution of funds from the escrow company.
A power of attorney executed in San Miguel is fairly straightforward, costs less than doing one outside of Mexico, and only requires a day or two's notice to the notary to draft it for you.
If you are a buyer, there are times when someone can sign on your behalf as an officious agent without requiring a POA. a power of attorney, but a seller should always have a power of attorney. A power of attorney can be given to a trusted friend or family member; some clients prefer to give the power of attorney to one of the attorneys at the notary’s office.
Whether you signed in or out of San Miguel, we recommend that your real estate agent work with the notary or one of his attorneys to draft the POA for you so that the notary will accept the language as is on closing day.
A power of attorney written by a notary in San Miguel will be in Spanish. When you go to the notary's office to sign, there will be a translator to translate the document for you if you don't speak Spanish.
Completing a POA from Outside of Mexico
If you're outside of Mexico, you'll want to have someone from the notary's office draft the document. Often, it will be sent to you in English on one side and Spanish on the other.
Once you receive the document, you have two options:
Option #1: If you live in the U.S. or a country that signed the Hague Convention, you can print out the POA document provided by the notary and take it to any notary public in the U.S. (or your country) and have it notarized. Once it's notarized, you also need to get that document apostilled and then overnight mail it to your agent or the notary.
If you live in the U.S. near a Mexican consulate, you can also simply go there and have them notarize the document.
Option #2: If you live in Canada or another country that is not a party to the Hague Convention, you will need to go to a Mexican Consulate. You will take the document that the notary sent you and have it validated. Each Mexican consulate has different rules and deadlines for validating a document. Some consulates will want to rewrite the document and ask you to come back in a few days to sign it. Others will actually use the document that you take. Check with your Mexican Consulate nearest you for requirements.
If you are a buyer, in addition to giving someone power of attorney to sign on your behalf at closing, you can also give a POA permission to have someone in San Miguel sign on your behalf to obtain your SRE permit and sign for the distribution of funds at closing.
Work closely with your agent, who can guide you through this process.