How do I remove the base price and only use options?

I have a product that I want to sell in three different sizes. At the moment it lists them like this ...

Price: £99.00
Available Options

* Size:
8x8" giclée print
12x12" giclée print (+£30.00)
20x20' giclée print (+£50.00)

I don't want it to list the price, I just want it to say

Available Options

* Size:
8x8" giclée print (£99.00)
12x12" giclée print (£129.00)
20x20' giclée print (£159.00)

So just state the size and total price of each option rather than saying the additional cost on a base price?

There are extensions to do this in the extension store. Please search the extension store for this.

Just use a price of $0.00 and options as your price