I'm sorry your friend is in this situation, but I have to agree with those who are suggesting there are 2 sides to every story, and this could be simple case of someone not measuring properly.
Seems like when this type of thing gets posted, people jump to the conclusion that the person who has no chance to respond has intentionally done something wrong. As someone stated, there are a LOT of things that can affect measurement from where they are standing to the type of stick they are using.
We also don't know what else was discussed in the agreement. For example, it might have been stated that the sale was "as is" in which case it doesn't really matter what height the horse is.
I can not imagine buying a horse and spending $1200 to ship it and not having a contract - especially if I had certain criteria - like height - that were critical to my breeding program. I think the lesson learned here take the time to get a contract. If the buyer won't put one together, do it yourself and send it to them to sign. There are a lot of people on this forum who would gladly provide examples. If they refuse to work with you on a contract, either walk away or assume the sale is "as is".
When I had smaller minis, I often offered the seller the right to have a 3rd party measure the horse before it was shipped. I was always amazed at how many people would pay thousands for a mini, but didn't bother with getting a second opinion on height (or having a vet check done. In the "big show horse world" you ALWAYS had vet checks done!)
Both parties could post , and for my friend it would only mean joining the forum and asking the question, she reads the forum. The seller is a forum member.
My friend was only wishing some guidance as to how to pursue the matter and I asked permission to get some feedback from a larger group of people who have more experience.
I believe that my friend felt that with the web site stating height, and the seller personally verified on follow up e-mail, and as well seller wrote the height on the transfer papers, how much difference could a contract make?
I expect a contract wouldn't be much of a deterrent since the legal costs to pursue the issue would not make sense and as we have seen in other cases a judgement can be made and the guilty party just refuses to pay.
That is why I couldn't get a loan in the U.S. without U.S. collateral being pledged and Americans are not liable to be loaned money in Canada, without Canadian collateral being pledged, since if there is a default you are usually out of luck.
It's interesting that in most cases with our little horses these measurement issues are always about having a taller horse than the seller states.
What difference does the type of measuring stick make? isn't 26 inches 26 inches?
I have not had the experience personally, that if a horse needs hooves trimmed or being "being fed more" for a long trip, or being measured 5 different ways, can be out 3.5 to 4 inches.
Are people still measuring to the last hair of the mane? Maybe this is where the problem is?