Whatever you do, don't use "wax liquidizer," which is just a fancy name for
propylene glycol or PG.
Friends that make carts using their distillate add only real cannabis terpenes. Some use other botanical terpenes, which provide similar flavors, but are not cannabis.
Real cannabis terpenes are available, although expensive, but your cart flavor will be the best there is. One friend bought his cannabis terpenes from a shop in Los Angeles.