Automate Harvest Invoice Creation

I need an automation specialist to recreate Harvest invoices in FreeAgent using Zapier or Make.com. The workflow must create in FreeAgent an invoice once I send one to a client via Harvest. To my understanding it's possible to do that but the invoice created in FreeAgent will be a draft. I need to move each FreeAgent invoice from Draft to Sent/Open without re-emailing the client, so invoices do not need to be raised twice for client billing and accounting reconciliation. This is an ongoing automation that runs once a month for around 20 invoices per month. I need a sensible estimated monthly cost to run it. Relevant experience includes Webhooks by Zapier or Make.com's Custom API Request module, FreeAgent API OAuth and invoice transition endpoints, and Harvest integrations. In your proposal, recommend Zapier or Make.com for this API request and explain why. Include examples of similar custom API workflows you have built. WORKFLOW REQUIREMENTS Trigger on new or submitted invoices in Harvest. Create a FreeAgent draft invoice with mapped contact information, line items, amounts, and tax rates. I am happy to manually create clients and tasks if needed in FreeAgent. Match each Harvest client to an existing FreeAgent contact ID, or create a contact when none exists. Use a secondary HTTP/API request to transition the invoice from Draft to Sent without sending an email. Test partial payments, multiple line items, and discounts. Provide a brief handover covering management of the API connection. IMPORTANT FreeAgent's native integration modules create Draft invoices only. The workflow must use the FreeAgent API transition endpoint to mark an invoice as sent silently: PUT https://api.freeagent.com/v2/invoices/:id/transitions/mark_as_sent. Please ensure before applying: - You will need to check that the above workflow is correct, because I generated it with AI. - Check that the work can be done - it is also possible that FreeAgent API wont allow for it - Provide estimate of your cost and of any ongoing cost I might need to pay for the automation - Not an urgent work