Last Minute Summer - Save up to 41% Off Grand Sirenis Riviera Maya Hotel & Spa, Mexico. Take advantage of this opportunity to treat yourself without breaking the bank. Book your stay at Grand Sirenis Riviera Maya Hotel & Spa and get up to 41% off. Terms & Conditions: Special offer valid until October 31, 2016. Stay period is from 1 September 2016 to 31 October 2016.