seller musiciansfriend on eBay I was sold an unplayable instrument which they refuse to exchange

I purchased the following item from eBay seller musiciansfriend:

Rogue RM100F F-style Mandolin Sunburst

When I took it out of the box, I discovered that it was unplayable. The action (height of strings from the fingerboard) was ridiculously high, and it couldn't be adjusted since the saddle was already all the way down.

I called them and told them about the problem, and the person who took the call was very rude and refused to help.

I then called the number for the Musicians Friend website, but they told me that they couldn't help me with eBay orders, and that I would have to speak with the nasty person I had already spoken to.

I then called Guitar Center, since they are the parent company of both of the Musicians Friend companies (although the first person I spoke with lied and denied that fact). They also referred me to the first person.

In short, I am out $120 with a useless instrument.

NEVER buy anything from these people.