traveling out of the country how does customs work $ bringing back alcohol from cabo san lucas mexico?

You are allowed to bring back two one liter bottles.

hallo,
i assume you are from the USA.
here are the customs requirements:
Tobacco:1000 cigarettes, a reasonable amount of tobacco and 100 cigars
Alcohol: 1 US quart

Are you American/Canadian or European? Each country has pretty close to the same limitations for bringing alcohol home. It will tell you that on your customs card. Read it.