Adult Halloween Party Game

We plan to have a Halloween party this year and found
A real good game to play! Well its more an auction than a game.As your guest arrive you give them an envelope with monopoly money in it, close to the end of the party you have item`s sealed in brown paper bags you have the guest bid on them using the monopoly money. When a guest buy`s a bag you have them open it and show everyone what they bought.
(HINT GO TO AN ADULT STORE AND BUY SMALL ITEM`S OR GRAB BAGS AND SPLIT THE CONTETS OF THE BAG IN TO SEVERAL BROWN BAGS.) I think this is going to be a blast!!! Can`t wait to see my friend`s reaction`s. Lots of fun.