A/R Batch Invoicing

We currently do not use the feature to batch multiple sales orders on one invoice.  I wanted to get an overview of how this is done or if someone has experience in this, could you give me a run down of it.  Our SAGE consultant mentioned you can not batch invoice the sales orders if they have different payment methods, and that is about all I know on the feature.

Is it just simple clicks of the mouse to select which orders you want to include in the invoice?  What if the indicator for which sales orders go on which invoice is found within the sales order, in the lines tab, how can you select the orders without going into each order?