valuator vs valuer

valuator and valuer both are nouns.

Word	Noun	Adjective	Verb	Adverb
valuator	Yes	No	No	No
valuer	Yes	No	No	No

As nouns, valuer is a hyponym of valuator; that is, valuer is a word with a more specific, narrower meaning than valuator:

valuator: one who estimates officially the worth or value or quality of things
valuer: someone who assesses the monetary worth of possessions

valuator (noun)	valuer (noun)
one who estimates officially the worth or value or quality of things	someone who assesses the monetary worth of possessions