In Trade Runner there is a setting called: Maximum stock quantity in Trade Me. Trade Runner will set the inventory of your products to the number that is in this field. 

How to set maximum stock quantity

You can find the Maximum stock quantity setting in Trade Runner under 'Settings - Trade Me - General' under the 'Your Products Section'.

Things to note

By default it is set to 200. If you have small changes in inventory you change this to a much lower number eg between 1-5, Trade Runner won't need to update your products on Trade Me as frequently as this can slow the updating of products down.

You can change this setting to any number (as per the arrow up/down) then click 'Update Settings' at the bottom of that page.  Then go to the Dashboard and click 'Upload to Trade Me' to update your listed products. 

Note that if the maximum quantity is say 5 but you only have 2 in stock, Trade Runner will respect the lower quantity and send a stock of 2 to Trade Me.

Also, if you set your max quantity to 1 for Trade Me, then you sell that 1, Trade Me will close the listing and relist it with a quantity of 1.