Box them. Keep them. Trust me. You will get a fraction for what you paid and when things change later and you want trains again you will have some. Trust me. I made the terrible mistake of selling my in the late 70s as interest changed to women full-time. Then a few years down there road paying a small fortune to replace the stuff I sold for a pittance.
I changed to O scale in 2010. I still have ALL my HO stuff and will not sell it or give it away. One day I may need it and if not its not worth selling. I still enjoy looking at it from time to time and use some HO scale buildings on my O layout.