You rely on there being other bands whose basses you can borrow?
That's a bit presumptuous. What if there's no other band, or their bassist is a jerk, like me, who isn't keen on letting complete strangers handle their bass?
A little off topic, but several years ago we had a fairly big gig for the band I was in at The Whisky and my drummer (high at the time, clean and sober now) didn't bring his drums! I thought he had to be joking, but he wasn't. He had a wad of cash and was banking our entire gig on the hope that the drummer from the previous band would let him use his set. About 15 minutes before we were to go on, he agreed to let my drummer use his set for $450. Needless to say, our drummer was out of the band after that stunt.

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