made-to-order vs custom-built

made-to-order is not a noun while custom-built is a noun.

Word	Noun	Adjective	Verb	Adverb
made-to-order	No	Yes	No	No
custom-built	Yes	Yes	No	No

As adjectives, made-to-order and custom-built are synonyms defined as:

made-to-order (noun)	custom-built (noun)
	an item made to the customer's specifications

made-to-order (adjective)	custom-built (adjective)
(of clothing) custom-made	built for a particular individual
built for a particular individual