Jojo,
You indicated in your original post that as a non-collector, you are interested in selling the collections.
I use the plural "collections" because of the different apparent ending points.
But you have already invested some of your own time and investigative instincts to figure out that in the case of the US collection, there is some pretty good material. I wonder if the collecting bug has not grabbed you, at least for those…. All of us would love for you to get into stamp collecting and have the enjoyment we do.
But, if you are still planning to liquidate, one of the first questions would be for you to consider how you want to do that. Do you have the time and inclination to develop sufficient expertise to start selling items individually or in sets on say
ebay, in order to maximize the financial return?
Or, do you want or need to minimize the time you spend on the liquidation process and want to just call someone to come look at the collections and then either auction them for you or buy them from you right then? The latter will likely realize the least financial return for you, but would be fastest.
We can give further advice on either course of action, the selling piecemeal or country by country over time on
ebay (or other platform) or getting someone to take care of it all for you. But let us know which of those broad brush alternatives fits your own priorities.
But know that with what you have in hand, you could have a great start on a very pleasurable pastime!
- Jonathan