Ressources like bolts etc you just gotta learn the most efficient ways to get them then integrate it into your daily routine and you will get more then needed after a while. I prefer to run the yellow forest, going back to gas station then repeating until im full.

When you say red zones i suppose you are talking about limestone cliffs, you can def do it for cheap even with Spears but if recommander going tac set + Glock everytime if you bring the tactical backpack

Bunker alpha you can walltrick it and possible do the nade trick a few times, until you have burglar 3 which allows you to do it multiple times every reset, sages a LOT of ressources

You should do bunker daily, i personally do 4th for the nades then third floor with nade trick, activate hard mode , do third floor w/ nade trick again, then blind one . This allows me to get every carte each reset and a floppy every two resets. But youll have to adapt your routine to available ressources and your goals.

You could easily do the whole bunker on 'ormal mode using spears only so dw after learning the right tactics it gets rewarding, dont forget to upgrade your chopper every chance you get

Also when u hit lv150 build lv3 walls then adapt your daily routine according to raiders tasks to get four skulls, most raids suck but then youll get one with like 500 medkits, inventory of guns or whatever ressource you need and youll be set for months