So basically a while ago I needed some gold on a alt on another server so I moved my main with 50k to my alts realm , first thing I did when I got there was transfer 50k to my alt on that server, then I contacted blizz by live support and told them I was really unhappy with my choice, I did this within a couple of hours of moving. I moved back to my original server with the 50k I transferred to my alt , and the Alt on the other still had the 50k also! So I made my money back from the refund and I made 50k gold!
Some things to note with this.
1. You will only get away with this once and should only be tried in the event that you actually need gold on an alt and a server move refund is your only choice, just incase they have fixed it you won't lose anything
2. If you have had a refund for a server transfer in the last 6 months they can refuse to do it, but 50% of GMs will help you if they are nice.
3. I haven't tried it with more than 50k,
4. Make sure you contact live support with 24 hours of buying and ask for a refund say you are really unhappy with your choice, it needs to be 24 hours so they can use Undo function as this is how it works I think.
Try it and let me know if it works
Thanks