I am trying to make arrangements for ladies from our chapter of Alpha Gamma Delta sorority to stay at the Marriott Rivercenter in San Antonio, Texas. We are wanting to check in on June 28, and check out on July 1, 2018. I'm not sure how to be sure that we are in the part of the hotel, where other members will be staying. I am a Marriott member, who is also a senior citizen. Any help is appreciated.