Zero price with product variants

-- url of the page with the problem -- : anvils.co.uk/alcosa-blacksmiths-forges-2...036-anvil-stand.html
-- HikaShop version -- : 2.6.4
-- Joomla version -- : 3.6.2

Please could someone help? When I have a product with multiple variants the price at the side of the product image appears as £0.00, can this be change to 'prices from ' and then the lowest variant price?

I have a product that is sold by the square meter and have set up the width/length plugin to calculate the price, however the product price is displayed as 0.00 each
If I enter the amount in the Retail price field the product displays Common price: AUD 3.52 Our price: AUD 0.00 each

Ideally I would like to simply set it as $3.52 per Sq M (or at least just the price - $3.52)

If I want to completely hide the price, where do I add the custom CSS as described in the previous post?
#hikashop_product_S001B_025_page #hikashop_product_price_main{ display:none; }