My husband and I bought our puppy on a Saturday. There were plenty of people out selling all kinds of breeds. I would not suggest a Sunday because Saturdays are quite busy and often gets picked clean. Also, people pack up early on Sunday afternoons. I have never visited on a Thursday or Friday, but I believe some vendors only do weekends. If you don't know already, you have to go on the animal side which is in a different part than everything else.
I didn't see anyone selling a puppy the 2 days i went.
Friday through Sunday of the First Monday weekend.
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