If I was getting one, I'd get two. (They're social animals.) Cute little ah heck. They prefer certain weeds to "lawn", hence despite the ad, they're not "great lawn mowers."
To cut and paste from another conversation on the exact same topic (pygmy goats):
I'd probably go for it if I were you, if I met the animals and they didn't have personality problems and seemed healthy.
Wife says: things you can ask the seller: (from the international fainting goat association site)
Vaccination history (what vaccines were used and when)
Deworming history (what dewormers were used and how often)
Does the herd have foot rot?
Does the herd have sore mouth?
Does the herd have any CAE?
Does the herd have any caseous lymphadenitis (CL)?
Does the herd have any Johne?s disease?
Does the herd have any abortion problems?
Production and background information include:
Pedigree information (should be on registration certificate or application forregistration)
Production record of does (years, number of kids produced)
Production record of any young goat?s parents
Birth status of young goats (single, twin, triplet)
Sellers should eagerly provide answers to all of these questions, so buyers should not hesitate to ask! If sellers are hesitant to provide answers to these basic questions, buyers should consider taking their business elsewhere!
Also, if you're getting goats, you'll want to take a look at some of the articles at
www.goatworld.com
Things you'll want to be aware of: what plants are poisonous to goats. (I killed one of our goats by absent mindedly feeding it an evergreen. I fed them xmas trees, so I figured, evergreens are fine. Had I said to myself, "Japanese yew", I'd have realized what I was doing up front. 1/4 cup will kill a cow - just nibbling on this common evergreen that people use to landscape will kill an adult goat pretty quickly. Oooops.)
The breeder/seller may not know the answers to the above questions, but they're worth asking. (It really comes down to how serious of a breeder the person is who's selling the pygmy goat.) Or, if the pygmy goat came from somewhere else nearby, perhaps you could take a drive by to see if it looks like the person cares for their herd. If the person selling the goat doesn't know the answers to the health questions (CAE, CL, Johne's, etc.), then ask, "have you ever had a problem with sick goats that wasn't diagnosed, or have you ever had any goats that died? A "yes" answer isn't necessarily a bad answer to the latter question - where you have livestock, you're gonna have deadstock (sooner or later.)
I'm not super familiar with pygmy goats and their specific needs. The goatworld site, though, contains a ton of information (if I recall correctly.) As some of the responses in the thread indicate, there's a wide range of personalities among goats, or how they socialize with the humans taking care of them. Bottle babies are generally the most friendly. But, just because a goat nursed from its mother doesn't mean it won't be friendly. Over time, you can usually get goats to become quite friendly toward people. Several in our herd came from a farm where they preferred that the goats not be overly friendly. (Most came from places where friendliness was one of the most desired traits.) All of the goats who tended to shy away from us at first are not quite acclimated to us and will readily approach us - it takes a lot of work though. (Animal crackers are one of the best bribes for goats.)