magento addons

we neeed 4 addon for magento here are the 4. first:? options for magento: When configuring a product, certain options need to get grayed out in different sections depending on selections made earlier, such as in the first customization field option 2 is selected, but in customization field 3 option 5 cannot work with that selection, so it would gray out option 5 in field 3 as soon as option 2 in field 1 is chosen, and states the ? customization field name that the selection stopping this was made in. second: Product image change: The product image needs to change depending on which option in a certain customization field is selected ? third: Floating Price box: There needs to be a price box that floats on screen bellow the right column in magento, and follows the screen as the person scrolls down, this is similar to some computer sale websites fourth:? ? Also, on the pricebox, there needs to be a power supply watt recommendation field, which shows which power supply is recommended by calculating the power requirements for products in the customization fields and adding them together, then picking a watt number out of a ? predefined list by picking the one closest to the calculated amount, but not less then it. these are the 4 but we have small buget so i like a bid and a price for each one.