First welcome to the group.. You now have the alum fever..
I have read that all the locks were keyed the same,, but our 72 Overlander each lock has a different key.. (real pain).. Several Airstream parts supply sell new locks with matching keys.. InlandRv is my pick at this point.
As for the tow wagon,, if I say anything other than it needs to be safe it will start a 34 page review of what is the best and what is wrong.. So will just leave it at the fact I would not wish to pull with anything else but a HD 1/2 ton,, or a full framed outfit like a Suburban.. It all boils down to is the TV in control of the trailer or is the trailer controlling the TV.. Proper hitch,, trailer loading,, and TV loading all matter for the end results.
The first steps,, and found on this site and worth the time to read are 100s of new owners and the steps they took and the order done..
My self the first goal was to make sure it was weather proof.. Roof,, windows,, and lose or missing rivets.. seals around the AC unit and roof vents..
If it has a minor leak its better to catch it now before you find reason to replace the floor or other high dollar high labor repairs.
Testing the plumbing,, service wheel bearings,, and inspect and adjust the brakes are also important.. The PO of my trailer said the wheel bearings were just serviced.. Right ,, about 10 years ago by the dry and limited grease and even used a paper clip for the safety cotter key.. Tires,, inverter,, battery,, then onto the furnace, water heater,, fridge.. 12 volt
system, lights, and 120 volt system..
Don't let this scare you ,, just make a list and slowly work down the line and check off items once done.. It's over whelming at first but once you get to the lower 1/3 of the lists you feel in control again..
Now what is listed above,, this is the easy part.. Once you think it needs a full polish job,, that is when the work starts.. Once you polish up part of the first pannel,, your stuck to finish it.. Mine took 80 hours.. I truly feel what I know now I would have just done a good acid wash and been happy..
The peace of mind knowing your trailer is ready,, and safe without any surprises once 400 miles away from home is priceless.