You cannot design a complex contract system that guarantee that somebody will manage your capital while you are out for three centuries.
Why should you? You don't really
expect to come back or anything. But you can entrust your wealth on somebody, and you can trust it is in his interests to maximize that wealth, and in the interests of the next guy to keep doing the same. The wealth would be there in some form or another. Offenhouse just feels he's capable of wrestling it (or a significant part of it) back to himself because of certain preparations he made.
Which would be pretty easy to do, really. Just put most of your original capital in a foundation, with the primary purpose of keeping your broker happy with the interests, and the secondary purpose (in small but airtight print) of dumping it all back to you when you resurrect. The portfolio would just fatten the foundation, hopefully.
Even under decent property rights there are always ways to cheat and any of his "stewards" has a pretty high incentive to steal from a sleeping man who can not defend himself.
They wouldn't steal from themselves, though. Offenhouse probably wouldn't be coming back within the lifetimes of the first half a dozen generations managing the wealth, if ever. So the wealth would be nurtured for its own sake, with some of it placed in suitable foundations or whatever while the rest would be for the caretakers to enjoy.
Come on, your argument that wealth evaporates by itself is a non-starter. The corollary that Offenhouse would be mentally deficient because he fails to believe in this is nonsensical. The idea that he shouldn't
contact his bank right after getting off the coffin is odd to the extreme. If the guy believes there is life after death if you pay enough, and is dead right on that
, why should you fail to respect his other conviction about being able to arrange for financial security of some sort?