There is a bug ingame that allows you to wear wt/mansion sets BEFORE fd12.
(offtopic:that of course if you have money to buy them- LoB female mansion is the cheapest right now 5kk all set)
What you need to do:
1. get into you inventory the piece of mansion that you want to put on.
2. Get next to it your old (same piece) cloth - be sure to not put any other on-pockets empty.
3.This is the part where you need to move fast.
Right click on your old cloth then rapidly double left click the mansion.
You should probably put it on in ...lets say in 5 minutes if you werent fast from the begging and now you got angry Laughing
After you managet to put it on it will bug you with a durability thing. Dont worry. Durability isnt decreased rapidly, its normaly.
note: WEAR A DECO! if gms wil spot you it will probably result in a ban....
Have fun :)