Challenging an Assessment

[Will Stewart]

Hi All

Looking at the latest assessment of my legal two-family home, it was assessed as "conventional" (likely because it hasn't been used as a 2-family in some time). Looking at comps, it is assessed 50% higher than any 2-family in the neighborhood on a price per square foot basis. 

My questions are, does this open up a can of worms letting in the assessor (if they do in fact come in during this process)? Is price per square foot a reasonable way to compare value in an assessors eyes? Do I have to accept this, since I recently purchased the home at above assessed value?

Thank you for the help, property is in New Hampshire.