What are the signs of a puppymill?

[Native New Yorker]

So I drove almost seven hours (roundtrip) to visit what may be a puppy mill.  A few of you may be able to confirm, so please tell me what you think.  I drove miles and miles to visit what online appeared to be a reputable breeder.  She responded to my concerns promptly, sent pictures, and seemed knowledeable about mini and standard goldendoodles.  I explained that I would NOT be purchasing with this visit but I wanted to see her facility and see if I could tolerate the mini's because I have mild/moderate allergies.  Upon my visit, she was not there but told me in advance that she would have someone show me the puppies.  When I arrived the young man had a carrier of two mini's that he took out of his car, which I thought was strange, and put them in a wired fence area so that I could "see them play" - his words.  I picked them up and they both smelled foul - unclean.  I asked how old they were and he said that they were 8 weeks.  I told him that I would like to visit more puppies and then he took me into a large shed that had 5 cages of various mini's, standards and puppies with their mom.  They were barking and the adults were hitting their heads on top of the cage.  I asked if they were allowed out of their cages and he replied that they are out quite often.  Then a lady came to feed the dogs and they went crazy, jumping, barking and running around in their cages.  The young man then told me if I purchased one that day that he was told he could reduce the price by $300.00.  I told him that I was not ready to purchase that day and would get back to the owner. I do not expect all breeders to have a pristine environment and I know that some will have more dogs then others.  Money and experience will determine how their spaces are kept. I'm aware of this, but the shed and the many dogs in a cage did concern me.  Since I have no experience purchasing dogs and this was the first breeder that I visited what do you think?

[Karen Klempel]

If it doesn't feel right, it isn't right. Sounds like a puppy mill type of breeding to me.