What exactly is a channel manager?
The layer between your inventory and the places you sell it. It keeps availability and pricing current on every channel and makes sure that when something sells in one place, it stops being sellable everywhere else. Without one, multi-channel selling means either overselling or deliberately holding back inventory.
Should I use an existing channel manager or build my own?
Use an existing one if it supports your channels and can express your pricing — it is far cheaper. Building is justified when your inventory genuinely lives in your own system, when you are the supplier others distribute, or when no product on the market handles your model. We will give you the honest answer, including when it is the one that earns us less.
How quickly does availability need to sync?
Fast enough that the overlap window is as small as the platforms permit, which in practice means real-time where a channel supports being asked directly, and promptly with retries where it does not. The right answer depends on how scarce your inventory is and what overselling actually costs you.
What happens when a channel's API changes or breaks?
It will, usually without notice. That is the argument for health checks, alerting, and someone maintaining the integration. We host what we build and watch it, so a broken feed is something we tell you about rather than something you discover.
Can you fix an existing setup that keeps overselling?
Yes, and it is a common request. It usually comes down to mapping, sync timing, or an unclear authoritative source for the count. Those are diagnosable, and the fix is normally cheaper than the overselling.