Turning on Quantities
To specify the quantities of an item, click the settings cog in the top left of the line item you want to edit and a sidebar will appear on the right. Click 'Show quantities' and click save and preview and you're free to edit the quantities and unit cost and it'll be automatically calculated in the total on the right.
Allowing your client to set the quantity
You may find yourself in a scenario where you know what product or service your client requires but aren't sure on the quantity. In this instance, you can allow you client to choose the quantity while viewing your proposal and sign it off without having to come back to you to make the changes.
To enable this feature, open up the settings sidebar like we did before to turn on quantities and then you'll see a checkbox for "Allow your client to set the quantity"
By selecting this option, your client will have free rien on the quantities they can add to your line item.
Setting quantity limits
In certain scenarios, you might want to set a minimum or maximum quantity to make sure your client orders enough to make it viable, or not so many that you aren't able to fulfil the request. Either way, if you'd like to set minimum or maximum limits on these quantities, you can check the box for "Set quantity limits" in the settings sidebar and set the minimum and maximum quantity that works for you.