Here's a fairly typical factory run for me:
190,000 roubles profit for that two minute raid, which will easily buy you an entire kit and then some. Of course, you'll want to play it slower and if you run into more geared players than hatchlings it'll take more time, but also more lucrative if you win the fight(s).
Peltor ComTacs are also a very legitimate alternative to helmets, I think Peacekeeper sells them at level 1. You hear sounds from further away and they enhance quiet sounds and decrease loud sounds. Only the best helmet can block rifle bullets, so the lower helmets only protect from melee, SMGs and shotguns. Can be good against scavs especially, but hearing someone sneaking will almost always be better.
Another quick run:
Fort armor, the thing I'm wearing and the second guy I kill has, is the best/rarest item in the game. It makes it very hard to kill you through the chest/arms, basically impossible unless you get shot by armor-piercing ammo and even then it can be 5-8 bullets to ruin it, and can only be traded for with 7 gold chains at max level traders. NPC scavs also very rarely have it, so if you find one then grab it and book it out of the raid. Unless you have AP ammo, shoot for the legs if someone's wearing it and the Fast MT helmet. If you have AP ammo, then headshots work well too. And that helmet alone is worth 200,000 roubles.