Regardless of the type aluminum metal used by Airstream over the years, they will all polish out to a mirror finish, when properly done.
Underbelly not included.
Clearcoat or plasticoat, is good for an average of 5 to 6 years, regardless of the amount of polishing or not, and then only if the metal is properly cleaned.
Clearcoat today, exclusive of any polishing, runs about $125.00 per running foot.
Many shops, such as ourselves, have stopped complete refinishes, due to local rules and laws.