An updated verison of this which includes stock checking and min/max validation can be found here: Stock Check and Max Quantity
This is a vQmod to add a maximum order quantity per product. Works in reverse to the minimum order quantity.
Default entry is 0 which means nothing happens and you can then set a maximum on a per product basis.
You will need to update the database in your phpMyAdmin to insert the 'maximum' field but I've included instructions for that.
If you don't want to / can't use the vQmod then you can always run through the xml file and use it as instructions to modify your core files.
Also includes updates to default template so you will need to copy those across to your template and/or change the file path in the xml file.
It's not completely tested but I think everything has been covered and working.
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