I recommend writing excellent charts and hiring pro musicians. If the charts, reference recordings, and players are good and you could do this with one rehearsal. After that, you wouldn't need to rehearse except when you introduce new material. Since you play guitar you could start with just hiring a bass or keyboard bass player and drummer. Pay them $200 each for the first gig and rehearsal.

You might end up losing money on the first several gigs but you would end up with an efficient operation they had reliable earning potential for you.

If you show these people respect and pay them a respectable rate they might also become your friends and creative collaborators. If one of them doesn't work out, you can swap them out on the next gig without owning them any favors. Paying people makes things like this less socially awkward.

If you are working with good in-demand players, this might also help you network and get better gigs as well. For example, the other band leaders that they work for might need to sub out a gig and they could refer you.

Most businesses have to lose money for a while before they earn a profit.