Options fixed pricing instead of each item

Hi,

I thought I would start a new topic instead of finding answers (i tried that but could not really find anything similar).

here is what I would like to do:

I would like to add options to my product and ask my customers if they would like 1 color logo on their tshirt or 2 color logo on their tshirt (i sell in qtys so the minimum qty is 100 $ 2 each)

if they select 1 color then I would like to charge them $50 fixed fee
and if they choose 2 colors I would like to charge them $100

right now when I add this option it adds $50 for each item to so when the customer checks out it show them $2+$50 for each item so the total becomes $5200 instead of $250.

Is there a module/extension to fix this problem?

I there are modules to charge fees on the check out page, but I want this for options

Any help will be appreciated

Anybody?

is there anyone who can help me on this?