To recover something, or to retrieve it.
Something that is lost and then found is recovered.
The adjective is indivisible.
Synonyms include flawless or ideal.
The word could be innovator, or in one sense a visionary.
Invisible
Something very old could be primeval (earliest, first) or primordial (oldest).
There is no one-word substitute in English for "son-in-law."
The adverb could be freely or voluntarily.
The word you want is florist.
Sportsmanship is a word substitute for spirit of game
The term is exorbitant. Something with a high price is called expensive.
The term for everywhere is ominipresent, but the adjective ubiquitous is used to mean something that is constantly encountered.