how to show summary on checkout page for multiple orders?

I am working on the Checkout flow (system) for the tablet device and it has 3 steps:

1. A list with existing orders (which were previously saved from another flow). The User should be able to select multiple orders from the list to proceed to the next step
2. Next step is Order Details. Here we can see the products(items) of each selected order. And my question is for this step. Can we show a summary for each order separately? Since it is important for us that at the step with Payment(3rd step) we can pay a different amount for each of them and choose different types of payment In terms of best practices and UI patterns..
3. Pay

Thanks!