[JamesC]

Its pretty simple to script, make a /buyclothes [Skin ID] command > check if the player is in the interior (IsPlayerInRangeofPoint || GetPlayerInterior) > Check if the Skin ID is valid (There's a function for it somewhere, just search) > Set the players skin and - money.

For something more advanced:
Click here

OffTopic: Wow, people still use ICQ?