Walk me through building a 3-statement financial model for [COMPANY/INDUSTRY]. Starting from these assumptions: Revenue drivers: [LIST], Cost structure: [FIXED/VARIABLE SPLIT], Capex intensity: [LOW/MEDIUM/HIGH], Working capital dynamics: [DESCRIBE]. Guide me through: 1) P&L structure and key line items for this industry, 2) Balance sheet mechanics and what drives each major item, 3) Cash flow statement from indirect method, 4) How to link the statements (the 3 key circular references), 5) Key checks to validate the model balances, 6) The 5 most important output metrics for this business type.