Yes most confuse the two...but they are actually quite different...one all metal (Beech 18..except for control surfaces) and one welded tube and wood construction....one with two vertical stabilizers and one with a single fin....
PS If I ever win the lottery I'm gonna buy the best H-18 money can buy! One still a taildragger...and with radial engines...(some later versions were converted to tri-gear and turbines and even single tails....)