Home buyers and sellers in the extraordinary Upstate of South Carolina trust and choose the Christie’s brand and the elite level of service that BlackStream | Christie’s International Brokers and our Elite Agents deliver. Leading Luxury Brand. Global Visibility. Unparalleled Service. Unrivaled for over 250 Years. With 1,200 offices in 45 countries and 32,000 Real Estate Professionals, we bring the world to your doorstep.