This one we have genuinely done.
Breaker Tools Pro is a full operations platform for live sports card selling. We built it, we own it, and we use it every week. That is stated plainly here because calling it client work would make our portfolio look deeper than it is.
It covers exactly the list above: pricing with real cost rules, inventory with cost and value tracking, show and listing preparation, live selling screens, sales reconciliation, reporting, buyer records and an assistant layered on top. The first useful tool was built in seven days. It grew into ten connected tools over the following month.
Being both the builder and the operator matters more than it sounds. We have had to use these tools on a bad night with money on the line, which is a very different test from a demo, and it is where most software design decisions are actually judged.