Apparently those armored cars are supposed to not be very resistant to fire, but on a progrom test it survived a very lot of molotov.
Anything that needs fire usually needs flamethrowers. They shoot eight shots a turn, and that damage really stacks up. If it took about 8 molotovs, you could have done it with one shot from a flamethrower.
Also, early-on, Assault Cannons are my answer to virtually every problem that flamers can't handle. They arc, the solid shot has some pretty hefty damage (80), and the explosive rounds are glorious(60 concussive, 5 AoE radius). That's usually the determining factor of whether I take the first progrom mission. Do I have my flamethrowers and explosive cannonballs yet? Then, you just snipe a few enemies, grab their weapons, and gtfo. Hopefully you get a grenade launcher or something.
There's way better weapons, but for early game reliability, those two are my go-to's. The flamers are expensive, but at least you can produce your own cannonballs fairly quickly. Then you've got fairly heavy scouts, backed with arcing fire support, and maybe a bit of melee and normal weapons to round it out.
Been a while since I started a playthrough, so I'll have to see what's changed.