MarketPress - single user can create multiple orders and pay for them with one checkout

Hi there,

I hope someone can help me. I am building a website for a client with MarketPress. As my title suggests, I need to allow someone to build a order, but then before going to the shipping/payment details page, they have the option to save their order and go build another order with a new order ID. Then when they go to checkout, they can pay for both.

I noticed that one of the order status is: 'received', so is there some way to use this to save an order?

In order to show what I want, it's probably best if you have a look and follow the user journey at:
http://myssdev.screencandy.co.uk/

1. The user is able to select a school from the list.
2. The user then chooses a class from a second list (you can choose 'year 5' for an example)
3. This creates a list of items for that school and class.
4. The user can add some of these items to the cart.
5. Also at this stage, I want the user to attach a the child's name to the order as well.
6. Now, when they click the 'Checkout' they can see a full ist of all items in their current cart.
7. At this stage, I want the user to be able to either 'Save order' or 'Proceed to checkout'.
7a) If they save the order the order gets the child's name and school attached, and the user goes back to the start of the process where they can create another order.
7b) Else if they 'Checkout' they will get to the shipping page, and can check out for the total cost of all their orders so far unpaid.

Is this possible? Can you give me any pointers? How much would your developer quote for custom building this for me!?!?

Hope you can help...

Neil