The ecommerce seller ops stack (2026)

The rule

This is the operations side of a US ecommerce brand — Shopify-first, Amazon as a channel, maybe a pop-up. It is not an ads stack. We will not rank AI image generators, writing tools, or media buyers. That catalog is Aiacent. If the leak is creative, leave. If the leak is overselling and a personal checking account, stay.

The default stack

• Store: Shopify if the website is the business. Square if the counter is the business and the site is a brochure.
• Inventory: native Shopify until a second warehouse or Amazon disagrees; then Cin7 or Zoho Inventory. Katana if you manufacture.
• Payments: Shopify Payments or Stripe. Know the in-person vs online rates. See POS and Stripe vs PayPal.
• Books: QuickBooks Online Plus if inventory hits the balance sheet; Xero if the advisor is Xero. Wave is a starter, not a SKU ledger.
• Banking: Mercury or Relay — payouts off personal checking.
• Payroll: Gusto when the first warehouse hire is a W-2.

Store and stock

Shopify plans start at $39/month on the public cards we reviewed. POS Pro is +$89 per location if the floor is real. Do not install four inventory apps to postpone Cin7; appoint one available-to-sell. Read the ecommerce inventory ranking before you sign a $349/month system for a side hustle.

Money

Processing is the tax you already pay. Shopify Basic in-person rates have been published around 2.6% + 10¢; Square Free in-person 2.6% + 15¢ as of September 20, 2026. QBO Plus is $140/month list because inventory and the close are the job. Gusto Simple is $49 + $6 when the first picker is an employee. This is not tax advice on inventory valuation.

What to skip

• An ERP because a podcast said NetSuite.
• A second storefront builder “for SEO” while inventory is a lie.
• AI ad tools as a reason to ignore payouts and COGS.
• Personal PayPal as the operating account.