If you have 50 amp service and the ceiling vent is "prewired" for an A/C, it should be an easy addition. If your trailer is 30 amps, then it's not going to be easy unless you devise a means to power it. Running two A/C's on 30 amps leaves nothing for the refrigerator, converter, lights, heat (electric or propane furnace), water heater, TV, etc.
It's "nigh on impossible" to run two air conditioners on 30 amps......
2015 F250 6.7l 4x4
2014 Cougar X Lite 27RKS