Bass 1) Fender American P or J. You can take your pick among the many models etc available; but, for many band leaders and other people you may work for, this is a standard. I would install a HipShot D-tuner and learn to use it.
Bass 2) Fretless; probably a Zon Sonus in some configuration, could be 4 or 5.
Bass 3) A "modern" 5 or 6 string. For me right now, this would be a Sadowsky 5 with either the WL configuration or a 24 fret neck. But, really, there are so many good options out there that many other cases could be made: Smith, A-C, Fodera, Nord, Spector, Roscoe, Alembic etc etc. Kind of depends here on preferences, budget, etc. I mean, if I win the lottery its a custom Alembic. But, I would still want the Sadowsky; so...
Interesting question; because a bass player should be able to cover a lot of ground with 3 basses. But, there are so many good choices with different things going on that are available now.
I think the reality is, for 90% of the posters on this site any single 4 or 5 string electric bass would do....

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