Sorry, I don't know anything. I'm a road rider looking into a mountain bike for trail riding and bikepacking. I am familiar with and quite capable of working on pretty much anything on a road bike, i.e. tuning derailleurs, installing bottom brackets, etc. So I know bikes, just not mountain bikes specifically.
Proposed budget of around 6 or 700 bucks. Used is fine. 29ers with front suspension. Decent components, but don't need to be top of the line (similar to maybe shimano 105 for road in terms of hierarchy). No particular brand loyalty. Must be street worthy as well (perhaps a front fork with a lockout feature).
Fire away. And flame away, if preferred.