Land and building are assessed separately, and only one may be wrong
Splitting the assessment splits the argument, and the land half is usually easier to win.
Your assessment has two components: land, and improvement — the building. They are produced differently and can be wrong independently.
Why the land half is often the better fight
Land assessment is largely mechanical: a rate per square foot or per acre applied by neighbourhood and size band. That makes errors visible. If your lot is assessed at $6 per square foot and comparable lots in the same class and town are assessed at $2, that is a clean, checkable discrepancy — and it needs no opinion about your kitchen.
Why building arguments are harder
Buildings differ in ways records do not capture: finish, condition, updates, layout. An assessor can always answer "that house is not like yours" and often be right. Building arguments usually need photographs, contractor estimates or an appraisal.
What this means practically
Look at the land line first. Divide your land assessment by your lot square footage and compare it to neighbours of similar lot size in the same class. If your rate is well above theirs, you have a narrow, specific and provable claim.
Say what you are claiming
A land-uniformity claim says the land is assessed above comparable land. It says nothing about the house, and a filing that implies otherwise invites a review of the whole assessment — which can move in either direction.