I normally say RUN from a salvage buy - but this is the 1 in 1000 that I'm going to say "great deal" on. To make a substantial savings I'm sure you are going to have to do a lot of the work yourself just because there are so many irritating little jobs to do. The only big downside you have to worry about is whether the clearcoat is dirty or discolored. Five minutes doing a "sample cleaning" might resolve that - and I have a last ditch suggestion. I let my water heater get pretty dirty once - and all of a sudden I had a propane soot problem on the outside. It wouldn't wash off with any car wash chemical, or windex, or Formula 409. As a last ditch effort I used Clorox Sink Tile and Tub cleaner. I feared it might scratch the clear coat, so I dabbed it on with a sponge, dampened the sponge and super gently working in one direction sort of wiped it around. 95% of the crud came off easily, the rest came off with a second application again wiped off carefully.
Even if the clearcoat is permanently discolored, fix the rest and enjoy for 5 years or so, and only when the clearcoat starts to fail, take it to a good refinisher and have it stripped and recoated.
I suggest that you name this unit "Phoenix" for the legendary bird that once every thousand years burns then rises from it's own ashes.
Hope you have a roofed area to keep it dry while you're working on it. My second worry, other than all the melted components on the top, would be seams and rivets leaking. At the plant they slather a lot of caulk on the inside of the shell, but the heat may have damaged it. They say it's a good idea to re-seal the seams once a year, but I never get it done in one day or even one weekend... lots easier to make it a 2 hour chore while hiding from direct sun! May I also recommend Captain Tolley's Creeping Crack Cure. I got obsessive and started going over every rivet on the roof. About 1 in 12 let the stuff leak through. I put a little piece of painters tape next to any rivet that leaked, and made a second application after the first had dried - only one needed a third application. That's a job I haven't finished because the weather turned to S*** (a four letter word for white stuff that falls from the sky), but I've only got one major seam left.
I hope you'll post with the progress - this will be an interesting thread. Can the A/C be salvaged with simply a new cover or have the boards melted too? What about the fantastic fans? Hey, go ahead and replace the skylights with good Maxim ones - you'll never regret that. Here's a thread:
Ditto for replacing the plastic bathroom vents for metal ones (if you can find them).
I've got quite a few customers who are in the fire and flood restoration business - if you LIKE the current upholstery take the cushions to one of those companies - it's infinitely simpler and better to have a pro get the burnt smell and soot out than trying to do it yourself. If you don't like the current stuff, get a good upholsterer to replace the foam and fabric in the cushions.... Airstream doesn't use the best foam, you got a bargain on the A/S, and you should get what you'll love for the next 10 years.
Curtains - I've never particularly liked the look of the Classic (especially the heavy curtain upon curtain with boxed valences) BUT the new 2015 has a system that is revolutionary AND has great privacy plus insulation. There's no reason the new Classic look won't fit in any other trim level - so if you like the look - consider it.
The hard surfaces inside should clean up pretty well. Again, BUY the right detergents/deoderizers from a fire & flood restoration service. (They all want to do the work and charge big bucks, but many will sell you the chemicals if that's all you're willing to pay for.) Cleaning up isn't rocket science.
You're going to have a huge bill for all of the bits and pieces you'll have to order from Airstream. At Alumapalooza a couple of years ago, the factory offered a discount on all parts bought during the event. On a big order like yours - ask for one - all they can do is say NO. Also UPS shipping is expensive - see if they can get everything crated and sent LTL (less than truckload) freight.