We wanted to put our own bodies on the line for this great cause, too, so if we can reach our fundraising goal by next Tuesday (two weeks after we started), then one of us will get a tattoo as well. It certainly won't be both our arms because, well, we're both wimps. Sarah doesn't even have her ears pierced, for goodness sake.
When people make a donation, they're invited to vote whether they would like Martin or Sarah to be tattooed. If we reach our goal by next Tuesday, whoever has the most votes will get the tattoo.
Five designs have been made up for each of us by Emma and the public will decide which tattoo they'd like us to get.
We had a say in four of the designs and the fifth is the other's name.
So, if Martin loses, he could potentially be branded with Sarah's name for the rest of time - a thought which makes him wake often in the night, screaming with terror.
For Melinda, it's not just about having the confidence to show her arms to the world but also about looking at her arms and seeing something beautiful, rather than the scarring that only reminds her of what she's lost.
Her ultimate goal is to wear a dress and actually feel comfortable and proud of herself.
• Can you help? Any donation is greatly appreciated - and don't forget to vote for whether you want Martin or Sarah tattooed.