The Multichannel Selling Setup: A Pre-Launch Checklist for TikTok Shop, Walmart, and Amazon

Expanding your sales footprint is a natural evolution for a growing brand. Whether the goal is to capture a younger demographic by setting up to sell on TikTok Shop, or to capture high-intent search traffic when you launch on Walmart marketplace, adding new channels is an excellent way to diversify your revenue.

However, flipping the switch on a new marketplace changes the mechanical reality of your back office.

Running a DTC site gives you complete control over the customer experience and the fulfilment timeline. Marketplaces, on the other hand, have strict, non-negotiable rules. If your back office isn't prepared to handle their specific requirements for shipping speeds, inventory accuracy, and returns, a successful launch can quickly turn into a logistical headache resulting in suspended accounts or penalised listings.

Before you add a new storefront, you need a stable multichannel selling setup. To protect your seller metrics and ensure your expansion actually drives profitable revenue.

Here are the 3 operational pillars you must build before you launch your next storefront.

1. Centralise your inventory pool

When you only sell on Shopify, your website is your source of truth. The moment you introduce a second or third sales channel, your inventory becomes a moving target.

If a customer buys your last available jacket on Amazon, your TikTok Shop and Shopify store need to know that the item is out of stock immediately. If your channels are relying on batch-syncs that only update every hour, you risk overselling. Overselling on your own site means a polite apology email to the customer; overselling on a marketplace often results in algorithmic penalties that suppress your future listings.

What to do: Before launching, ensure your tech stack includes a centralised operational hub that sits below your sales channels. This hub must treat all your stock as one unified pool, pushing real-time inventory updates to every connected marketplace the second an order is placed anywhere in the network.

2. Map fulfilment to marketplace SLAs

Marketplaces protect their customer experience fiercely. When you launch on Walmart Marketplace or Amazon, you are agreeing to their Service Level Agreements (SLAs). These dictate exactly how fast an order must be acknowledged, picked, packed, and shipped.

If your warehouse team currently relies on manually exporting order spreadsheets at the end of the day to send to your 3PL, you will likely struggle to hit the tight fulfilment windows required to maintain top-tier seller badges.

What to do: Your order routing needs to be completely automated. Before launch, set up specific operational rules so that when a marketplace order drops, it is instantly routed to the correct warehouse or 3PL, prioritised based on the shipping SLA, and the tracking data is automatically pushed back to the marketplace without human intervention.

3. Prepare for complex financial reconciliation

Every marketplace has a different fee structure, payout schedule, and method for handling sales tax. If your finance team is used to the relatively straightforward deposits from a single DTC storefront, adding multiple marketplaces can make the month-end close complicated.

Trying to untangle which portion of a Walmart payout was revenue, which was tax, and which went toward fulfilment fees is incredibly tedious if done manually.

What to do: Ensure your multichannel selling setup clearly maps financial data from each specific channel directly into your accounting ledger. You want to be able to pull a report that shows the exact contribution margin of your TikTok Shop versus your Amazon store, factoring in the specific costs of selling on each platform.

Connecting the dots with Plug & Play integrations

The biggest hurdle brands face when expanding isn't usually a lack of inventory, it is a brittle tech stack. Historically, connecting a new marketplace to an existing warehouse system required custom API coding. These custom links are expensive to build, take months to deploy, and frequently break when a marketplace updates its software.

This is where a Retail-First ERP System like Brightpearl by Sage provides a distinct advantage for growing merchants. 

Brightpearl is a central operational hub designed specifically for omnichannel retail. It replaces a fragmented back office by natively unifying your sales channels, inventory management, order routing, and financial accounting into one single source of truth.

Instead of relying on fragile custom code, Brightpearl uses native, Plug & Play integrations. This means you can connect your operations to Amazon, eBay, Walmart, or TikTok Shop in a matter of clicks.

• Orders flow in seamlessly from every channel into one centralised dashboard.
• Inventory is synced across your entire network in real-time.
• Fulfilment workflows are automated to keep you compliant with strict marketplace SLAs.

Expanding your brand shouldn't require rebuilding your back office from scratch. By laying the right operational groundwork, you can turn on new channels with the confidence that your infrastructure can handle the growth.

Ready to simplify your multichannel expansion?