I've managed to add text to the price for a single product, but I can't find any way of adding to the price of a variable product.
Basically, I need to declare the price including and excluding the tax, and I've managed to do this by adding text and a formula to the main price. But I cannot find any way to even slightly alter the price for variable products. If it was not possible, even inserting (ex. VAT) would do.
You could use CSS to insert Ex VAT after the prices. Depending on your theme your prices would all be wrapped in a specific ID or class, so it should work. http://www.w3schools.com/cssref/sel_after.asp