My verrucas are annoying me!!?

ok so iv got loads of verrucas on my feet, iv got 2 on my left foot, but 1 seems to have gone, and about 5 on my right foot. iv tried using Scholl seal and heal Verruca removal gel, but this didn't help at all. iv heard you can get them removed by your GP, and they freeze them with Liquid Nitrogen. does this really work? and is it free? or do you need to pay, and how much is it? or is it just easier to buy Verruca Sub Zero? witch i believe freezes them as well. thanks