If mercs are too expensive for you try slaves for example 5 homesteader females equipped with 223 pistol just owns for traps(compared to other slaves) they have no armor but if you face 1-3 guys 223 pistols will do the job anyway thus female homesteaders have 101 hp and that is a lot for a slave , i have a big gunner slaver

the rocket launcher or lsw compliments the 223 pistols great. Then again you can equip the bitches with grenades it's like omg eternal knockdown , or if you really want to have fun get plasma grenades , slave children and trap with them the guys won't even realize what hit them before they die.
Weird fun stuff i haven't tried yet.
Cheap melee mercs with super cattle prods , or unarmed with super power fists!
Dogs equipped with dynamite( not sure if this is possible ) , dynodogs or smthing ?