Army Of Two

- Well, when you get far enough into the game, there is a mission where you blow up a bridge to assassinate a target . This has a checkpoint right after you run back down, so you can repeat this easily for about 10k I think.

- For weapons, Don't bother with the minigun/grenade launchers and most of the shotguns.

- For Primary: Aug or PKM. In the beginning I think the AK is a good starter.

- Secondary: .44 Model 29 (fully upgraded will one shot most enemies)

- Special: SVD

- I used a FAMAS through almost the entire game and just upgraded the hell out of that, picking up the DAO-12 in the last level and pretty much killing everything in one shot. Unless you really care about those Kill 250 Enemies with X Gun achievements you don't really need to ever change weapons in that game, since they all end up looking and performing almost exactly alike after upgrades. Just pick your favorite gun and roll with it. You can even use the default gun until pretty late if you want to save up for the Minigun. About upgrades? I never noticed the shield do anything of value, but I guess it can't hurt to have. Anything that boosts accuracy is nice, and silencers can be helpful since you'll almost always have your partner on aggressive and you'll want him to maintain aggro.

- As for your partner, his guns changed over the course of the game and I don't know what caused it. You can try trading weapons with him one mission, then buying a new gun for yourself next mission and see if it sticks.

- You'll get enough money through one run of the game that you can buy cheaper versions of weapons, upgrade them, and then buy the better version, and upgrade that one.