Hi, it is not customary to tip the casa owner. They earn a very good living, probably among the best in Cuba and there is no reason or obligation to give extra.
I sometimes bring a bit of spare clothing to Cuba. Some t-shirts or kids clothes and trinkets that I have no use for. I give it out to people I know. If I dont manage to give it all, I just leave it in the casa. This is a usual occurance with many tourists. Other than that, I dont leave monetary tips.
Take care,
Mario
