We have a set list. We practice the eventual list plus a few extras. Sometimes good tunes get cut, but the week of a performance, the list is set and there are no audibles for extraneous tunes. We've played one encore since I've been there. There are two folders, practice and performance. Only the performance folder attends the concert. I feel sorry for you having to lug all that music around. I used to play in a church band that did that. 500 charts and any song could be called up at any time. We played 8 different tunes on any given Sunday. I took my file "bucket" home to practice the tough songs (the ones George Rawlins recorded!!) and lo and behold an audible was called. The other trumpet player wouldn't let me look on his music, he turned it away!
Anyway, The conductor isn't going to change, none of them do, so maybe a little cart for your horns and file "folder". This is what I used for years and it is still in good shape!
That's a great-looking cart! There are smaller, but flimsier folding luggage carts available for cheap, or you could simply use a small carry-on size suitcase.
