The minimum system requirements for the local business data deployment option are quite hefty. The Azure Service Fabric cluster -that will host AOS, Batch, Data Management, Management reporter, and Environment orchestrator services- requires a minimum of 16 instances in total for both the production acceptance topologies. For the backend infrastructure, that can be shared across the production and acceptance topologies, an additional 5 instances are required. This excludes your file storage/SAN (Storage Area Network).
Doing the math overall, you are looking at a total number of 21 instances with 104 CPU cores and over 400 Gb RAM.
You can download the full Dynamics 365 for Finance and Operations, Enterprise Edition local business data system requirements here: https://www.microsoft.com/en-us/download/details.aspx?id=55496