Honestly, my advice is keep some stuff. Keep all the essentials because one day you WILL come back to this hobby whether you want it or not. Sell all the expensive stuff, but keep stuff like chemicals, test kits, buckets, ro/di, racks, mag floats. The first time i "got out" of the hobby, i let everything go to a newbie. When i came back with my new build, i had to buy all that stuff again, and even though it wasnt really expensive stuff, it all added up. Now even though i dont have a tank, i kept most of my stuff because il come back in a few years.