Am I the only one who works at a company where the developers are the only ones who understand the product that the company is selling?

Try working at a company where no one has a fucking clue on what is happening. My place is kept afloat purely because of Google Ads

They want me to write them their own custom eBay in a month's time.

@Jase I wouldn't mind building it from scratch as an application itself but having to integrate it with the database that's in an appalling state and trying to glue things together because nothing has any relations... My point is that its bad, very bad and they don't want to fix what they already have before building something on top of it.

@Jase I kinda disagree with your point where developers are the one who knows the product so well since we are the one who is making it. Developers don't normally own the product the business does so I would said the boss should know better than us unless you are the business boss, also the developer :D