Think long term not short term. Selling everything that he has leaves him pennyless and unable to support a life in exile, and that would be the ideal story to tell Masipa if he tries to get bail after his conviction. But Arnold can support him. There was no reason to sell his home in the middle of the trial other than to reduce his assets to try to claim that he could not support a life on the run if he decides to flee.
A single man with no children, no job, no income, no connection to his community, in his 20's, a world traveler with a passport, convicted of murder and condemned to 15-25 years in a SA prison is most definitely a flight risk.
Here is a link to very similar murderer trying to get bail while on appeal after her conviction. Wollie and Mangena battle again, Mangena wins of course. Spoiler alert: she was denied bail:
http://www.saflii.org/za/cases/ZASCA/2013/1.pdf