Fifth, you've been a great help; I also lacked a beanstone and knew EXACTLY which one I missed (even though I searched that area abotu 8 times before, but whatever). Also, finding those hidden attacks... I can't believe I missed that cave the first go round.
Anyways, here's my piece of advice.
Right after you reach Little Fungitown for the FIRST time, IMMEDIATELY equip both Bros. with that badge that deals damage proportionally to the number of Mushrooms you have, then spend all your money on Mushrooms, Super Mushrooms, etc. Keep buying nothing but mushrooms as you continue through the game, except maybe the best clothing equippable. I, so far, have more than TRIPLED my characters' attack power with this trick. That is, I once hit 25, now the same attack does something like 80. Add this to that item that double EXP if you take no damage, and also the item that doubles the damage you give and take, and you can gain levels VERY quickly (I.E., at the rate of about 7-10 per hour).
Works very nicely for me. On Hermie III, for example, I went from requiring about 30 turns to win the first time I played to requiring FOUR.
~I.S.~