Is there a module to modify orders manualy and change prices

Im looking for a module where its possible to:

1.
If you have a order made on 1. january and the prices change 2. january. If you for some reason want to change anything on the order after the price change, opencart automaticly updates all items with the new prices. This is a bad solution. Do any one know a quick fix for this?

2.
Lets say a customer ask if he can get somekind of extra service by phone, and we agree on 10$ extra, it should be possible to add a line in the order with manual text and value without creating a product.