Trade offer

A Trade offer (engine class: trade) is X4’s representation of buy offers, sell offers, and trade orders (deals). The same trade type covers all three — distinguished via .isbuyoffer / .isselloffer / .isoffer / .isorder flags.

Properties

Existence + availability

Property	Type	Description
`.exists`	boolean	Trade exists
`.available`	boolean	Trade exists and is available
`.isbuyoffer`	boolean	Is a buy offer
`.isselloffer`	boolean	Is a sell offer
`.isoffer`	boolean	Is an offer (buy or sell)
`.isorder`	boolean	Is an order (accepted deal)

Parties

Property	Type	Description
`.buyer`	container	Buyer container
`.seller`	container	Seller container
`.owner`	container	Owner (seller or buyer)

Ware + amount

Property	Type	Description
`.ware`	ware	Trade ware
`.amount`	integer	Trade amount
`.desiredamount`	integer	Trade desired amount (may exceed affordable)
`.offeramount`	integer	Trade amount + reserved
`.offeramount.{$object}`	integer	Trade amount + reserved for $object
`.minamount`	integer	Minimum trade amount
`.transferredamount`	integer	Wares transferred for this trade
`.destroyedamount`	integer	Wares destroyed for this trade
`.volume`	integer	Total volume of trade amount
`.offervolume`	integer	Trade volume + reserved
`.offervolume.{$object}`	integer	Trade volume + reserved for $object
`.minvolume`	integer	Volume of minimum amount

Price

Property	Type	Description
`.price`	money	Total price of trade amount
`.unitprice`	money	Price per single unit
`.minprice`	money	Total price of minimum amount
`.relativeprice`	float	Current price between min and max (-1.0 to +1.0)
`.quantityfactor`	float	Current/average price ratio
`.hasdynamicprice`	boolean	Price not fixed (e.g., player-set)

Stock level

Property	Type	Description
`.stocklevel`	float	Trade amount / target amount ratio
`.stocklevel.{$amount}`	float	Amount / target amount ratio

Price locking

Property	Type	Description
`.ispricelocked.{$container}`	boolean	Price locked on $container’s trade partner

Bundle / unbundle

Property	Type	Description
`.bundle`	boolean	Flagged for converting ammo/units → wares on transfer
`.unbundle`	boolean	Flagged for converting ware → ammo/units on transfer

Mission integration

Property	Type	Description
`.ismission`	boolean	Trade spawned by mission cue
`.missioncue`	cue	Mission cue used
`.tradeoffer`	trade	Source trade offer (for orders)

Free trades (for mission rewards)

Property	Type	Description
`.buyfree`	boolean	Buyer doesn’t spend money
`.buyfree.{$object}`	boolean	Free for specific buyer
`.sellfree`	boolean	Seller doesn’t receive money
`.sellfree.{$object}`	boolean	Free for specific seller

Common access patterns

”List a station’s sell offers"

<set_value name="$offers" exact="$station.tradeoffers.sell.list"/>
<do_for_each name="$offer" in="$offers">
    <write_to_logbook text="$offer.ware.name + ': ' + $offer.unitprice + 'Cr'"/>
</do_for_each>

"Get a station’s current sell price for a ware"

<set_value name="$price" exact="$station.sellprices.{ware.advancedcomposites}"/>

"Check if trade offer is part of a mission"

<do_if value="$trade.ismission">
    <write_to_logbook text="'Mission offer: ' + $trade.missioncue.name"/>
</do_if>

"Reserve trade amount for a specific buyer”

<set_value name="$reserved" exact="$trade.offeramount.{$myShip}"/>

Common gotchas

⚠ The same trade type covers offers AND orders. Always check .isoffer vs .isorder before assuming meaning.
⚠ .amount reflects current state; use .offeramount.{$object} for reservation-aware accounting when working with specific buyer/seller.
⚠ .price is the TOTAL — use .unitprice for per-unit calculations.
⚠ .relativeprice ranges -1.0 to +1.0 — not 0..1 or percentage. -1 = minimum price, +1 = maximum.
⚠ Mission trades may be .buyfree or .sellfree — your economy mod’s accounting must handle these.
⚠ .tradeoffer links orders back to source offers — useful for understanding fulfilment.

Common actions

Action	Purpose
`<create_trade_offer>`	Spawn a new trade offer
`<remove_trade_offer>`	Remove an offer
`<transfer_money>`	Money transfer (part of trade flow)
`<transfer_inventory>`	Ware transfer (part of trade flow)

Ware — what trade exchanges
Container — owns trade offers
Cargo — what trades modify
Faction — owner of trade contracts
Reward calculation — how mission trades price

Trade offer is the central economic abstraction. Stations expose them as .tradeoffers.*, missions create them programmatically, and the price mechanics drive the entire X4 economy.