G&G Instrument Corp. has sold its 59,000-square-foot flex office building at 466 Saw Mill River Road in Ardsley for $4.75 million, according to Colliers International. Representing the owner in the deal was the Colliers team of Ian Ceppos, senior managing director, vice chairman Alex Jinishian, executive managing director Al Gutierrez, and associate Cameron Paktinat. Avon…