Aduana in La Paz Baja-operating hrs?
 

I'm in Santa Rosalia weighing my options for which day to take the ferry from La Paz to Maz. Is the Customs office open 7 days a week or just on sailing days? And, should I get the TVIP a few days in advance or just the day of sailing?

Oh, and if there is anyone taking the boat (probably Sunday Sept 8) I'd like to share the cost of a cabin with someone.

Thanks