Cabaret style shows have a certain element that can be lost in a theater especially when trying to balance pizza or something on your lap after it’s been run down a long hallway to the theater than passed down some form of say continental style audience pattern. In attempting to do this alone, you might loose the focus much less the spirit of the play.
Same with a show backstage in unless the stage is huge, having trouble keeping the audience safe. Though if the stage is large enough, it could form a really unique production in this style of show. This said however ask yourself is it because of the style of doing a show backstage you would be doing this or because of the ease in the technical aspects of the show?
The school cafeteria I would think the more normal place for it to be done, than again, it’s hard to get the ambience of a cabaret in a happy industrial lunch room - technical problems aside. One might look into some German beer halls in how in some ways the long instead of little round cables can be appropriate, but Formica and colored plastic/easily folding up tend to make the suspension of disbelief a little harsh. Much less a large room with windows
etc makes it hard to narrow the focus short of scaling it down some. This and the disruption to the school’s lunch room people would cause endless trauma for them.
My old school had an over flow lunch room with a simple gymatorum type of stage in it we could take over for the yearly dinner theater production of bad pizza and soda in doing more of a cabaret style of show. By it’s nature it was also fairly close to the kitchen but not close enough that it was disrupted by it. This type of setting also allowed the large cast of actors - a cash cow in itself to both act in the show and learn their alternate professional trade. I remember Cabaret, Egad the Woman in White and some western show with Wild Bill in it done in this way.
Lighting wise, I remember an ancient
dimmer system in the hall with only a few circuits, a small scaffolding set up for the lighting and sound booth, some booms and a few permanently mounted pipes hung from the ceiling.
Were I considering this production for your school having not seen the place, I might look for a small hall of a room that can be closed down to student traffic for a week or two. Perhaps a small gymn, or large classroom either of which near the lunch room hopefully for the utility of re-warming the pizza. Short of this, might it be possible to close off part of your lunch room with some flats and or portable walls? Than just erect the pre-built scenery and some form of stage.
For tech stuff, I assume the sound system in a more simple form should be fairly easy to move, just a question of some speakers. Given it’s cabaret, you could possibly go without mics. For lights, transport a follow spot or two and put them on the scaffold with the control gear. Light board should be easy enough to transport along with some booms. If you don’t have enough booms, borrowing from other schools might be an easy option. Assuming you have a fairly simple
light plot, fixtures from the stage could than be mounted on the booms with some shoe box dimmers either the production buys during it’s second or third year of production or for now, something you rent so you are not stuck with them given something goes wrong. The shoe box dimmer than plugged into wall sockets becomes a simple way of control along with perhaps some switch assembly for larger loads the maintenance people set up for you. They might also be able to hang some simple pipes from the ceiling in making it easy.
Really, beyond the rental of the dimmer packs in using them for things a simple switch or two won’t control nicely, that should beyond the food, costumes and advertising be the only real expenses. They often are good money makers especially when the cast is large. It’s also fun to get out of the theater once in a while.