i want to get 1 or 2 snails that dont get to big and dont reproduce asexually , i just want to have them and THEM ONLY, i dont want tons of them coming out of no where.
Tough choice as nearly all snails will reproduce no matter what you try unless they're not asexual and kept alone. Even females of some species can hold sperm for their entire lives without a male present.
Apple/Mystery snails are easy to keep without the problem of rapid reproduction. Here's a picture of one of my 'mystery' snails laying eggs. As you can see they're above the water line in clumps the size of medium black berries. They're easy to locate and remove. I've only seen 3-4 clumps altogether within a period of 7-8 months. I suppose it varies from snail to snail.
ive had two black mystery snails in my tank for about 6 months and they are great. they help keep the tank pollution to a minimum and i havent seen one egg or baby snail. Up until a week ago when i bought a dojo loach i havent had anything in the tank that eats snails either.