Melt the bottom layer ingredients and spread in a 9x13-inch pan. Cool.
Boil for 5 minutes the sugar, margarine, and milk from second layer ingredients. Add the peanut butter, marshmallow creme and vanilla. Pour this mixture over the bottom layer. Sprinkle with roasted peanuts.
For third layer, melt caramels with the water. Drizzle over the peanuts.
Melt the fourth layer ingredients and spread over the caramel.