CoStar Group provides commercial real estate information, analytics and marketing services, maintaining extensive databases of property listings, transaction data and market analytics used by commercial real estate professionals. Its data and analytics platforms are widely used by brokers, appraisers, lenders and investors who need detailed information on commercial property characteristics, ownership, lease terms and comparable transactions to make informed real estate decisions. CoStar also operates online real estate marketplaces, including Apartments.com and other listing platforms, extending its business beyond data and analytics into consumer-facing property search and marketing services. The company's revenue is largely subscription-based, tied to the ongoing data and analytics needs of commercial real estate professionals, giving it a fairly predictable, recurring revenue stream supplemented by advertising and marketing revenue from its consumer-facing listing platforms.