Previous research in Smart City technologies has been narrow and system-specific in both their orientation and focus. Specificity creates the homogeneity of systems architecture that, while beneficial from an experimental position, is entirely incompatible with the broader needs of a system standard. The current review seeks to examine existing research and their outcomes and summarize research milestones in the intersection of three domains of blockchain technologies, IoT capabilities, and smart city solutions. Based on the inclusion criteria, eighteen studies extracted from 6 academic journals contained some form of experimental or model-oriented solution and offered a distinct advantage over other proprietary research in this field. The SLR has divided the central concepts and structural solutions illuminated in the blockchain-IoT-related, smart city research conducted in the past four years into its core components: a structural solution of issues of security and authentication in the IoT, a tangible application of smart contract technologies for decentralized smart negotiation and a means of permissions-based performative oversight and administration. Heterogeneity and proprietary technologies will revise IoT's scope and capabilities and capabilities. However, this intermediary role of the Blockchain has been proven in many experimental and exploratory works and offers a significant advantage over prior structural limitations.