Yes the house clearance route can be beneficial even if they given you a pittance in general terms. The issue with sentimental value needs to be managed sadly.
Most of the charities will not take furniture without the appropriate fire retardant markings, electrics without PAC testing labels (available on RS Components and Amazon etc) and so on making it ever more difficult. MiL was moved from a home to a flat for her last years and the work to reduce her belongings prior to the move was a serious effort. Even using a rental van to go to the dump was a swine of paperwork and questions. So much for embracing recycling.
MiL is stage 4 now so not looking forward to having to do the same at some point soon. Just keep enough to make the house look staged and not empty I guess.
I still have two boxes of Dad's RAF stuff that needs sorting and has done for a long time. Some wonderful photographs.