I have a few naive questions regarding the BCN deal and I hope someone can shed some light. First of all, does it usually require multiple days of stay in BCN or just 1 or 2 days to turn around back? Secondly, how and what area do you book for hotel stay? Also, I assume non-US citizens (e.g., green card holders) would need apply for a visa thus should account for additional cost in time/money.