But why paint the Titanic Museum? For Stephen, it's partly due to advice from his grandfather to take photos of things so "you can look back" because they "might not be here" forever.
He said ongoing development around the Titanic Museum means the view he painted won't be the same in the future.
"With the likes of the Titanic [building], there's development going on and things will happen."
"It's hard to take for a lot of Belfast people when they're going to drive over the M3 and they sort of can't see it anymore."
As for the Edge, Stephen said the guitarist was very down to earth.
For a photo after the auction, the artist "went to stand at the other side of the painting and he said no, no, come over beside me, and he got me to put my arm around him and he put his arm around me".
"It was quite a lovely moment."
Belfast based tech entrepreneurs Mark Dowds and Roger Johnston, plus 24 fellow business owners, are set to trek across Ireland - scaling 26 mountains along the way.
The businessmen have raised close to £1m for the Cancer Fund for Children.