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Thanks for sharing the context. The workflow and impact are clear, and I understand why re-keying estimates in Dashboard is a blocker.
As of today, I don’t have a timeline I can share for Estimates API support unfortunately. The closest workaround is to model the proposal/estimate in your own system using the Orders API for the structured details including line items, taxes, discounts, catalog references, etc. then create the Square invoice through the Invoices API once the customer approves. That can help avoid re-keying the invoice data and handle it in a programmatic way, but it is not a full replacement for a true Estimates API: it won’t create a native Square Estimate in Dashboard or provide estimate-specific status tracking.
We’ll pass this feedback along to the product team again. I appreciate the detail here. It’s definitely a helpful example of where an Estimates API would unlock more invoice volume through Square.