Nevertheless, in a case where the multi-signature wallet suggestion is not feasible, I am considering arranging my portfolio in different wallets according to the heirs I want to inherit them. As time goes on and when I guage their level of mental maturity, I could even give them access but with specific instructions never to temper with them until I am no more. This is because I feel it is better the rightful heirs access the funds than some third parties pulling a fast one on me and my heirs. This is just a possibility and I might still adjust it.
I am a little bothered by what you seem to be suggesting, at least in terms if a lot of time might pass between giving the instructions, and I suppose I could assume that you are checking the validity of the wallets periodically, such as 1 or 2 times per year, because if several years pass and the keys and the method has not been checked, it could become problematic..
Well, what I am saying is a kind of simple and direct. Let me put some specifics to my point for clarity sake. Assuming I have 3 heirs that I want to transfer my asset to and I already save like 6 BTC that I want to share equally among them. I could just make 3 different wallets and transfer 2 BTC to each of them. Thereafter, I will give each of them access to the wallets and mandate them to keep the information safe and never to withdraw anything from the wallet until I'm gone as that will be my gift to them. Any further Bitcoin I buy will be shared in similar proportion and sent to those wallets as well. I will set a bench mark of like 16 to 18 years as the age they must get to so I am sure the money will not affect them psychologically. This is necessary because exposing children to certain kinds of money have a way of affecting them negatively like I stated before. Besides, the aim of wealth transfer will be defeated if the wealth affect then negatively rather than be a thing of help to them.
Of course, another way could be to describe the method, but also provide the back up seed (or whatever method is being used), so even if they are having trouble figuring it out, they still may be able to get some technical assistance from some random hacker (hopefully trustworthy) to figure out derivation paths or whatever might be a possible snag in getting at the wallet showing the proper balance of 0.00451376 BTC or whatever the correct amount contained therein might end up being.
I will still have access to the wallets even after giving them access too and periodically I will be checking the wallets to see that everything is in order. 1 or 2 times per year that you suggested is a good one and enough to know that all is going as planned. Well, I don't completely see how the services of a third-party will be needed because I already stated in my earlier post that I will make it a duty to teach them the basics. If I don't need such services, then I don't see why they should. Remember, money is involved so I am confident they will be will to learn the basics which is enough for them to protect the asset and all the sensitive information as they will do with their normal banking details. But then, looking at it from another angle, I can keep that as contingency plan and in this case, it will be someone I have some level of trust in just like you suggested.
There is a pretty wide practice of the use of trusts amongst rich people in a lot of places around the world, and even if there is likely some jurisdictional variance (and even various hurdles along the way), trusts are considered to be kinds of private conveyances of value/property, that are set up while you are living and you can even have a trusted friend administer once you pass.. or you could already have it going before you pass and you could be the administrator of it while you are still living..
I surely don't know all the nitty gritty between the kinds of trusts (revocable and irrevocable) that could be set up, but you ultimate describe whatever terms that you like within such trust including who the administrator is (and of course who the various beneficiaries are) and usually the administrator would receive some kind of a fee that you would describe within the trust. and I would imagine that you would not want your trust administrator to work for free because they might not carry out what you want if the terms do not fairly compensate them for carrying out the trust terms and maybe even describing how expenses, if any, are paid from the trust.
I was actually excited seeing this wonderful suggestion from you. This method could also be very good especially when one want to set aside part of the wealth for charity. Even though it is not still very clear if the established trust that I know can take up digital assets like Bitcoin, but there is still chances it will be possible.