Javascript Calculations on Oscommerce Homepage By Gigi06144 on Sep 5 Max Bid: Open to fair suggestions

Please see this page:http://shutters.virtual.vps-host.net/premium_wood.html
This page is a "calculator" for a Shutter Store. On top of the page, we have these options:
Shutter Type
Louver Size
Color
Mounting Options
then we have 10 different lines for each room the user wants to order shades for.
We will be calculating 2 different prices with javascript:
Price
Ext Price
Price - is like a "base price" or an "each price". Here is the Calculation:
PRICE = SQ FT of Shutters (rounded to the nearest whole number) * $20 (sq ft Price of Premium Shutters)
For example, on the first line, if the user needs some shutters for his kitchen and the dimensions are:
Width FT = 6
Width IN = 3
Height FT = 5
Height IN = 4
(WIDTH FT * 12) + (WIDHT IN) = 75 INCHES
(HEIGHT FT * 12) + (HEIGHT IN) = 64 INCHES
75 + 64 = 139
139/12 (rounded to the nearest whole number) = 12
12 * $20 = $240
$240 = PRICE
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EXT PRICE = PRICE * Qty + Louver Price + Color Price + Mounting Option Price.
The values for the Louver Price, Color Price and Mounting Option Prices are already in the dropdown menus.
 
This requires knowledge of HTML and Javascript. Eventually we are going to integrate this form into Oscommerce. If you have good experience with Oscommerce, that would be helpful.
Can you start this project today? It should not take more than a couple of hours for an experienced Javascript programmer.
Thanks!

Requirements Interview Answers:

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