Add 2nd AC to 2016 25' FC ducted version

[Trailer]

HI,
I recently asked the factory about adding a 2nd ac unit to our 25' Flying Cloud FB as we spend time in hot climes and the 15,000btu Dometic is insufficient. I was told they had no idea what the cost would be as they haven't added ac to a newer model with ducted ac system.They did give me a "ball park" figure but I could buy another trailer for that.
So I'm looking for advice on how to approach this. Should I get the construction plans from Airstream so I can see where the ducting and electrical are laid out?
William

[Glenritas]

A second A/C would also require an electrical upgrade . One solution would be a switching system to alternate the the 2 units, Another solution would be to add a second 20 amp inlet circuit for the second A/C . Or upgrade to a 50 amp service ( most expensive and difficult ).

[Trailer]

I had a 2015 25' FB and it had 6 ducted vents in the galley cabin and 4 ducted vents in the sleep cabin (one in the head) and the trailer stayed very cool even in the desert in 115* weather. I was told that "that trailer" was originally set up for 50amp and 2 ac units but they ended up not selling it as such. The 2015 ac unit was the same 15000btu unit as in my 2016. I'm going to start by adding 3 vents in the galley area and 2 vents in the bedroom, and possibly enlarging the return vents. I don't have that measurement for the return vents but will find it and maybe enlarge it as well. If you happen to know what the ducted return vent size is for a 2 ac unit model I'd appreciate knowing. This may be my best solution to prevent expense and leaks.