Even that though, it depends on what gear you need. Add up the cost of a good varied effects pedal laden board, power supply, patch cables, recording interface, headphone amp, cab simulator, tuner e.t.c. and, if you have decent gear, you can't be far off.
On the gig payment front, how many gigs do you need to do to pay for the other tools you use, your basses and your backline? IEM's? Lights? PA?
Your comments would suggest being a musician is eye watering in itself...