We have configured Service Plan that has three additional resources. Now in Customer Control Panel and in Online Store it is possible to buy this Service Plan without any resources, and these three Resources are optional. However, what we need is that it would be required to choose any of these three resources, two resources or all of them, and any amount when initially buying this Service Plan, i.e. it should be not possible to place the order if none of these resources are chosen.
In current BA implementation it is possible to configure resources to be mandatory only by setting Webshop Display Type to Radio Button, but with Radio Button it is possible to select only one resource, and impossible to adjust required amount. A feature request for required functionality has been submitted as #PBA-52339.