Funnily enough my band just played a show which wasn't organised very well so we had to do our own sound, it wasn't a great mix on stage, I could barely hear my keys player, but I just needed drums. The front of house sound though went down very well, so yea maybe just do it yourselves, we had a friend doing levels and they didn't have any live sound experience. My own input, don't use a headstock tuner, or phone, It sounds simple, but my bassist has on multiple occasions been tuning on stage with one. Even when the volumes not up it just looks unprofessional. Buy a pedal or borrow one, it'll save you time and everyone else.