1. a professional up here in QLD, charges $600 to $800 cash, depending how bad machine is.PLUS the decals u buy ya self.

2. it is not that hard. i watched a mate do it.
i have listed very basic steps but a pro can fill in the blanks.

remove playfield from machine.
remove headbox from cabinet.remove all computer boards etc from head box.
if u use goo off or a simalar product, it helps to get decals off.usually a orbital sander is used til full cabinet n headbox is back to a raw wood look.important to get all old glue off cabinet where old decals were applied.
then a sealer is applied after bogging with wood putty any dings, deep scratches etc.
apply new decals.put it all back together. 

FIND a experienced forum member who lives in your area who wants to help you.offer them the appropriate amount of cash and learn how to do it ya self for next time.