I'm not a collector, but here is what I can best determine about this set of 5 books: Title: Les Miserables Author: Victor Hugo Publisher: New York, George Routledge and Sons, Chicago McDonnell Brothers , 1886. I thnk it is First Illustrated Edition. Hardcover. Contents clean. No major damage, just old. Early but likely not first printing. Five quarto (7-1/2" x 10-3/4") volumes bound in publisher's green cloth with printed paper spine labels. According to the title page, "with illustrations from designs by De Neuville, Bayard, Morin, Valnay, and other eminent French artists." Text in English. 5 volumes. I would say excellent condition, given that I can't imagine how such old books could be in any better condition, but given the age, maybe it is called "good" condition.
AI says this: Based on recent market listings for the 1886 George Routledge and Sons 5-volume set of Les Miserables by Victor Hugo, your set is likely worth between $500 and $650.
While you mentioned it might be a first printing, this 1886 Routledge edition is actually a "First Thus," meaning the first time this specific illustrated English version was published by Routledge. The true first edition of Les Misérables was published in Brussels in 1862.