The fee schedule covers government charges only. The larger costs are usually corporate record work, financial statement preparation, premises commitments and professional review.
The petition is not the expensive part
Filing charges should be confirmed against the current USCIS fee schedule at the time of filing, and premium processing where it is elected is a separate charge with its own rules. Those numbers are knowable.
The costs that surprise a rural business are the ones the petition assumes rather than lists: cleaning up an ownership structure that grew informally over two decades, having financial statements prepared to a standard an outside reader will accept, committing to premises before the outcome is known, and paying for the professional review that catches a broken qualifying year before it is filed. Budgeting for those first, and treating the government charges as a small line item, produces a more realistic picture of what the branch actually costs to open.