If you're going to overhaul the hubs and bottom bracket, the specialized tools (without which you cannot do the job at all so don't even try just buy the danged tools) will cost you way less than the labor. It's an easy but slow job, and when you're paying by the hour, it ends up costing a whole lot. If you have the correct bicycle-bearing-specific tools, it's not difficult, just a bit fiddly and slow the first few times you do it. If you don't, it's an impossible nightmare. Buy the tools. There are no good substitutes for bicycle cone wrenches, headset wrenches, and bottom bracket tools. Yes, they're way more expensive than they should be. That's because literally nothing else works.
No, there's no torque specs for bearing cones that I'm aware of, and I wouldn't trust them if they existed, because circumstances alter cases. You adjust them by feel, and the differences between "too tight", "too loose", and "ahhh..perfect!" are not subtle. Just play with it, and you'll figure it out pretty quickly. Plus, it's almost impossible to do permanent damage to cup and cone bearings on the repair stand. It's possible, sure... but you'd have to really be trying to screw things up. (Like using a cheater bar or an impact gun or something.) It's riding them maladjusted, dry, and dirty that makes them die.
Working on bikes isn't really that hard. It's the weird incompatibilities and
14 competing standards for everything that will trip you up. The actual turning-the-wrenches part is pretty straightforward. (As long as you have the tools. Buy the tools.)
--Shannon