The correct market to sell stuff changes too quickly for that to work. And sometimes older people don't even know what markets exist. My father collects some th

The correct market to sell stuff changes too quickly for that to work. And sometimes older people don't even know what markets exist. My father collects some things but has never ever used ebay for example. Plenty of collections might be valuable internationally but not valued locally. Also in my experience the best collections are for the love of it - collectors often don't care about the value and often don't even know the value. They might care about rareness or uniqueness but not $$$ directly. Also the value of many collections is unknown until far in the future.