Wow, leaving the basses would make me more nervous than leaving the amp! I'd bite the bullet and get a nice Mono Dual Bass Gig Bag and take the two basses wth me. That bag might be also be able to hold the amp head too. Although, that's probably going to be way more than you want to schlep back and forth to rehearsals.Yep, 2 basses, pedalboard, head and cab!