Hi Op, based in Mexico doing destinations.

So, the truth be told, the things about doing some destinations is that we are doing it illegally. We move as tourist. For example if you go to Bahamas, you can spend like $500 up to $1000 in permit fees.

I have a few North Americans and European photographers friends that come to Mexico and work here without permits.

You can do the legal way and the illegal. I would advice you to do the legal way. You are on time and its not expensive. Just contact your closest Mexican Consulate and check the requirements for temporary vista for work.

Technically you require a permit. But again I'm not a lawyer so don't take this as legal advice. Just head to your Mexican Consulate or Embassy and fill the permit to work. They can give you all the requirements.

Los Cabos, Mexico is almost 92% Expat town. Almost everything is in English and everyone charges in USD.

Just my recommendations,

Do you have insurance policy to cover your equipment and liability in a foreign country? If not, get one.

Don't forget that some resorts in Mexico will charge over $1000 use for external (per external vendor). Probably your couple knows this.

US Customs

Also you need a custom's permit too. Especially if you bring more than one camera into Mexico. This is not for Mexico, this is from the US customs.

You need to fill the US customs of equipment that you are bringing outside of the country. It’s required in order to prove the ownership of your equipment. Otherwise you maybe subject to import tax. You need Form 4457 (Personal) because you can leave the US with over $6000 in gear but you need to prove that you own that gear. So need serials, etc.

If you are a business and using more than $1500 in gear you should fill CPB form 4455 that is reserved for commercial products and equipment taken abroad.

Anyways if you need later a second in Mexico, let me know :P