You just gotta know where to go and when to go. When I head to NCR which is an obviously safe town I head there at day to trade items. and when it is night time I head to the dangerous areas to grab some resources like junk,wood,fibers,pelts and head to my tent and wait till mornin' to start selling the stuff I have. Once you get the levels up and your outdoorsman is at 100% you rarely get in those dangerous encounters and start rakin' up some caps.