Thanks so much to longtime reader KD for leaving a comment on the You Tell Me page just now about this one!
Now through 11/1 on the Zoya website, BOGOFREE any of the polishes on THIS PAGE with code FBG at checkout. Also, you'll get free shipping on orders $20+. Terms and conditions here.
Buy four $10 polishes = $40
After BOGOFREEE promo = $20 + free shipping ($5 per bottle)
Buy six $9 polishes = $54
After BOGOFREE promo = $27 + free shipping ($4.50 per bottle)
Thanks again, KD, for the great tip!