The biggest issue would likely be his water. Since you won't be there, if he consumes the supply of water and runs low, that could be potentially dangerous for him. Mine is content to sit in the soil for days and not touch his water if I keep his soil moist enough, so if you can figure that out, it might solve this issue. Of course, if he's the type to poop in the water dish, you might have a whole different issue to reckon with.

If he's like my pacman, he'll go to a new spot after pooping in the old one, lol. But it's hard to say since you don't know his personality/quirks.