Special price each certain amount and delivery time option

Hi all,
There are two questions (well, could be more in the future :blush:) I'd like to ask to the forum.

How to make a special price for special item, when the buyers order at certain amount?. For example, for item A, if the buyer order 9 pieces, the price of each peace is 100, but if he buy 11 pieces, the first 10 pieces cost 95 each, and the last one costs 100. And so on. special price will only valid for the first 10th, first 20th, and so on.

How to create delivery time options? I mean, just before the order process finish, I need to know when (date and time) buyers want the stuffs need to be delivered to the buyers' address. Delivery services here require a delivery time so that when the courier come to the buyers' address, buyers are at home. for example, Monday, 17.00 and so on.

Thank you very much. :smile: