This is not a simple answer, so here goes!
Is this a new build or a remodel?
There are many different types of insulation. Each have their pros and cons and uses depending what part of the country you live in. Are you in Minnesota where it snows like the Dickens and is brutally cold in the winter, or at my Dump in the Desert where it hardly ever rains?
Here are some sites which cover cost, "R value," and types of insulation.
If you are performing a major rehab, there will be inspections along the way - insulation will be one of them.
Not knowing where you are, these sites provide broad, general information within which to explore more fully before making the best decision for your home and climate.