I'll give this a shot.
Here are my airstream expenses. Keep in mine I did all the labor.
Purchase price........................................$2100
New A/C and Fridge ...............................$1440.
Update/certify OPD valves on tanks..........$146
Lexan for new windows ...........................$25
Repair locks ..............................................$132
Plumbing repairs ......................................$376
LP, CO detectors ......................................$75
New tires, repack bearings ......................$420
New water heater .................................. $260
Vinyl floor .................................................. $50
Cabinet doors ..........................................$114
New upholstry and blinds ........................$609
Misc rivets, vulkem, gaskets .....................$200
Polish and cyclo ........................................$600
Misc, screws, camping stuff, sewer hose...$1000
So that totals out to about $7500.
I knew the condition of the appliances were shot, the fride, a/c, water heater, etc... So I knew what I was getting into.
Mine was considered a basket case for sure. But at least I had a solid floor and no major dents in the skin. But not much else

Still need a new furnace, and new shocks.
Should help someone thinking of getting into an airstream an idea what they are getting into...