Gaijin Market Price Watch

Small userscript for watching Gaijin market sell, buy, and auction pages for items that drop below their observed usual price.

How It Works

• The script scans the current market view on an interval, and also reacts to market search requests made by the page.
• Each item gets local price history stored in browser localStorage under gaijin-market-price-watch:v2.
• Prices are stored as raw Gaijin price integers. Displayed GJN values are calculated as rawPrice / 100000000.
• The usual price baseline is the median of the saved price samples.
• The displayed average price is the arithmetic average of the saved price samples.

Deal Detection

An item can alert when all of these are true:

• It has enough history samples, or its price is high enough to use the sample bypass.
• Its current price is at or above Min price GJN.
• Its current price is below the median baseline by at least Alert if below %.
• It is not hidden by the trophy filter.
• Its notification cooldown has expired.

Panel Fields

• Alert if below %: Required discount below the median baseline.
• Min samples: Normal number of saved samples required before alerting.
• Bypass samples GJN: Items at or above this price can alert with fewer samples.
• Min price GJN: Ignores deals below this current price.
• Hide trophies: Hides trophy items and skips alerts for them.
• Refresh sec: Automatic scan interval.

Alerts And Button

The panel shows the last deal that actually triggered a fresh alert. The Open deal button opens that same displayed deal in a new tab.

If a scan finds no new alert, the last displayed deal stays visible until another fresh alert replaces it or history is reset.

Storage

The script keeps up to 40 samples per item. If browser storage fills up, it compacts saved history to fewer samples and retries saving so scans can continue.