I'm kinda just posting this open ended question cause I really don't know much about bike maintanence and am open to any/all advice for someone new to bicycle maintenance. Also, as a broke, young person, with no bachelors and few job prostpects, any income is warmly welcomes, so "flipping" bikes is something I'd be interested in; as gas gets more expensive and the apacolypse looms ever nearer it seems, bike maintenance may be a very important skill.
I recently began to upgrade/maintain my old 80's Raleigh steel frame (my new bike, which required little of either was stolen). I converted it to single-speed (seems to be very popular right now), and learned a little about maintenance by tweaking the chain-tensioner, getting the right chain length, installing the front chain ring, etc.
Anyway, I am just rambling now, but I have a chain tool, lock-ring removal tool, pedal and cone wrenches...
Is bike maintanence a profitable endevour? I am not very mechanically inclined, but like working with my hands. I'd also be interested in painting bikes as part of flipping them. I'd be interested in any thoughts. Thanks.