I do not have much of a problem with snails or slugs anymore. They are the bane of Hosta gardeners, and indeed, I have fought a few battles with them in the past. Now whenever I find I have some, which is rare, I bring out my big guns.
What is my secret weapon? Slug and snail killer with the active ingredient of iron phosphate. The last I bought was made by Ortho and I found it in the lawn and garden section of a local store, but there are other brands such as Escar-Go! and Sluggo to name a couple.
How does it work? The iron phosphate shuts down the snail or slug's digestive system and it starves to death. You do not see them laying around dead, but you gradually see less damage, then eventually no more.
How do you use it? Sprinkle it around affected plants and the snails are drawn to. I recommend hiding it under the plants so that it does not become expensive bird feed.
What are its advantages? It is organic and gradually reverts back to the soil. It is fast and easy to use. It is safe to use around pets and kids. It lasts through rain and watering without needed to be reapplied. It works better than anything else I have tried. In the early days I went through quite a bit, but now that they are under control, one box has lasted several years and will likely last several more.