Here's a little tip... in Sanctuary craft lots of large water generators in the river and get your water up to 150-200 or more if you want... do this and you'll start seeing 100-150+ purified waters show up every so often... with 10 charisma you can sell these waters for 10 each and just buy your ammo instead of having to scrounge for it. The more water generators you build the more water you get.. you can pretty much afford to buy all the components and ammo you need. At 10 charisma 10mm and .45 rounds cost 4 each. Shotgun slugs I believe are 6 each as are some of the rifle rounds like .308. Make sure to go to sanctuary regularly and take the waters out and move them to your safe storage.. my storage is in a building I built on the roof of the overhang right next to the workshop.
Too boost charisma temporarily... wear a suit that boosts it 2, hat that boosts it 1, and pair of glasses that boost it 1, boosting it 4 just from clothing.
Getting enough aluminum and copper is harder to do than finding ammo.... scrounger perk is NOT needed unless you spray and pray with automatic weapons.
The gun and armor mods have let me craft far superior weapons and ammo than I would have found in the wild. I have them both at level 2 right now, and science at level 1. Take the points you want to put into scrounger and use them for lockpicking ... terminals are of minor importance.. I'd say I pick 10-15 locks for every 1 terminal I need to hack and then I haven't come across anything so important it warrants blowing a couple of skill points I could use in more useful perks like armor/weapons crafting or damage output, damage resistance, stimpack effectiveness, etc.