- Sentry Management Corporate Office - 2180 West SR 434, Suite 5000 Longwood, FL 32779 - Phone: 407-788-6700 Fax: 407-788-7488 Sentry Management Inc. Corporate Office: 2180 West S.R. 434, Suite 5000, Longwood, FL 32779-5044 Phone: 407-788-6700 Fax: 407-788-7488 e-mail: info@sentrymgt.com Sentry Management is an Accredited Management Organization (AMO) of the Institute of Real Estate Management ...www.sentrymgt.com