Base price should be same as per options - open to bidding

Base price should not be 0 zero. 1). When change option then price should be show only of selected option. No + or - with any other options. 2). Price of lowest option must visible on the product tab. So if customer view product on homepage then price lowest price will be show. 3). Desciption of the product must change when option change. Or 2-3 Lines from the description change when option change. 4). If I get similar to parent+child select option similar theit will be good for me. 5). Extension should be in OCmod mode and I'm using opencart 2.x version and customize theme. So let me know.