Human bandit making challenge

[Half-orc Bard]

Hey playgrounders I can't make balanced monsters for my life and In my campaign I'm having the players kill bandits and they are going into a bandit and I was wondering if anyone could make a regular bandit and how many I can put up against 4 lvl 10s and a challenging fight of the leader bandits(I would like for him to have lvls in scout and rouge) a wizard(necromancer or illusionist) and a cleric or other healer. Thanks

[Flickerdart]

Conventionally, 6th level is around the peak of regular human ability. A gang of 6th level bandits would be like Olympic champions turning to a life of crime (which would be a great premise, but I digress). 10th level is way superhuman - a 10th level party casually binds supernatural monsters, travels exclusively by teleport and communes with gods. The only way for them to bother with bandits is if the mafia don turned out to be a demon or something. Levels in Rogue? Try a murderjack (http://www.wizards.com/default.asp?x=dnd/fw/20040828a). A wizard buddy? Disguised ethergaunt. Cleric? An eladrin bound to serve against its will.