Some Items will be intentionally overpriced with the intent of lowering until bought, so as to gauge how much (or how little) people are willing to pay for specific Items. So just keep an eye on the prices of things that you want but are too expensive for your tastes.
Nothing here will ever be priced in GB, unless the item being sold is valuable enough that the equivalent value in SB would be excessive. Which to note my value cap before considering GB pricing is between 2000-3000 with a hard cap on 3500.