Everything sounds great, but as has been said by others, I think the idea of buying multiples for individually increasing costs only makes partial sense.
There should be a function where you can buy a specific quantity or all/max for the current price.
So if there are 7x loaves of bread available for purchase and their price is 20 denars each, you should be able to purchase 5x for 100 denars (20 each) Once that transaction is complete, there will be 2 loaves of bread remaining and the new cost would be higher e.g. 28 denars each.
You could do this by designing the trade interface as a list with their quantities next to each purchasable/sellable item, like the trading screen in games like Patrician
OR
You could do this with the same trading window as M&BII, but you select all the items you intend to buy and then click a "Confirm Trade" button, rather than each click being it's own transaction.
Looking forward to the game and thanks for the regular updates.
