My 6-piece Deep ForestWalnut Mapex kit for sale. Includes all hardware and Zildjian cymbals. I never traveled with them. Studio work only. I'll take pictures if interested. No cases. ABSOLUTELY A GREAT SOUNDING KIT!!!!
I'd look at what used kits have gone for on E Bay, Reverb and other fora. Type best price+ the desired search term in your search bar and see what comes up. Another scenario is 35-40% or so of list price, unless you're dealing with round badge Gretsch, Sonor Rosewood Phonics, or Brady drums, which seem to hold their value, given that the typical dealer markup seems to be 100%. Good luck, in any case.
Pictures and prices are essential. Go to eBay, enter your kit in the search bar, then specify "sold/completed," and see what your kit typically sells for. Hold your breath, because the drum market is very depressed and bloated now, and Mapex has one of the lowest resale values of all the majors.
Sell your cymbals separately and individually. Use eBay again to figure value.