There are currency exchange banks in San Miguel de Allende all you need is your passport, however, it is best to make the exchange before crossing the border or in advance for the best exchange rate.
Banks, a few shops, and restaurants will be closed November 20th for the holiday. On this day, Mexicans remember and celebrate the Revolution which started in 1910 and lasted for about ten years. The holiday is sometimes referred to, el veinte de noviembre (the 20th of November). The official date is November 20, but nowadays students and workers get the day off on the third Monday of November, no matter which date it falls on.
Be on the watch for a parade and other civic events. The actual legal holiday may fall on the nearest Monday or Friday, making a three-day weekend. Ask locally for details. In recent years, many stores and businesses in Mexico have been creating promotions around this holiday, naming it el Buen Fin ("the good end," as in weekend), and offering sales and offers similar to the way Black Friday is celebrated in the United States.
Bohemian vibes. Good walking, thick sole shoes are essential. Long sleeves during the day and a warm sweater at night.
Car rentals are not necessary to get get around the main plaza and parroquia. Walking is the preferred mode of transportation. If you are thinking of planning a trip out of town you can book a ride with a shuttle service or use a taxi.
Each museum has different fees, many galleries are free to the public. If you have a student ID bring it along for free entrance to those museums that do charge.
November 22 - Musicians' Day - It's actually the feast day of Santa Cecilia, (fun fact Saint Cecilia is the Bride's confirmation saint) but since she's the patron saint of musicians, music makers of every kind gather tonight at midnight in front of the Oratorio church and offer up an all-night serenade to the Virgin.