MargaretB.
A small item, but they all help. You said "We get out, go into the trailer for the leveler, check the interior levels". I use a 6"-8" bright orange level, but I leave it on the floor of the trailer right inside the door. It travels there all of the time. For front to rear level I use the metal door sill and for side to side there's a spot about 8" in from the door sill that I use. This cuts down getting in and out of the trailer several times cuts down using the steps several times if there area bad knees or hips and speeds up the over all process.
I also use two little magnetic levels on the tongue. No they aren't as accurate, but they get me in the ball park, then I'll go back and forth to the trailer door to use the larger level for the final check.
Bill