With the deepening of power system reform and the advancement of the "Dual Carbon" goals

as the core nodes of urban energy systems

buildings are gradually transforming from passive energy consuming terminals to active prosumers with regulation capabilities

making their direct participation in electricity spot markets an inevitable trend. This paper explores the distributed trading mechanisms for building users in electricity spot markets. Firstly

it outlines the evolution from passive response to multi-level market architectures

including Peer-to-Peer(P2P) trading and virtual power plant(VPP) aggregation. Secondly

it analyzes the dynamic gaming strategies and cost optimization algorithms for building microgrids based on real-time pricing(RTP). Finally

the application of key digital technologies such as blockchain

edge computing

and artificial intelligence in ensuring transaction trust and supporting decision-making is discussed. The paper concludes by identifying current challenges in standardization and data security

providing theoretical references for the digital transformation and low-carbon development of building energy management.