Beat. I started off by grinding enough for the shotgun and I completely missed the loot in your house and meeting the sister because I did not think I was allowed to go there. Also missed out on the free sleeping and kept paying for the inn. Kind of does not feel like being kicked out of home if you can still sleep there. I never bothered to rent any vehicles for the entire game. I did complete everything in the beginning and barely managed the big cannons boss; I had to use piercing shells and discovered how amazing they are. For the rest of the game I scraped by on the cheap, relying on piercing shells to disable bosses. I skipped many purchases and went with the plan of just using whatever I found for free, and I avoided using the temporary protectors.
I skipped getting the ambulance for a long time because the boss was so difficult, so the girl spent much of her early time on foot and I thus gave her the best gear. I did buy an smg grenade and found it so useful that I kept it until near the end. I went the wrong way and ended up at Devil's Tower sooner than you are meant to and got a lot of sweet gear. I was not able to beat Zeppelin though. I then went back using all those levels and upgrades to get the ambulance, which did not get much use because I found the Tiger tank soon after. So I had hunter in the tiger, mechanic in the mosquito, girl in the buggy and towed the ambulance. I stumbled into a trader camp during a sale and bought 3 smash horns and got back to Devil's Tower the way you are supposed to. Zeppelin bugged out as I was fighting him for an hour without winning. I looked online to see his hp; 1000. Given I had a sweet piercing shell crit for 600 he should have died ages ago. So I loaded the state, ran into him randomly just a few steps away, he fled and then I was able to beat him.
I swapped the buggy out for the LAV and went into battle with Gomez with the Tiger at 0 armor; totally unprepared but still won without much trouble. By the time I reached the final dungeon I was using the white, red and tiger tanks towing the LAV. I went back to buy the Abrams but the guy wanted my entire savings of $300k. Like hell. I used a walkthrough to see what I missed, finish up most loose strings (never killed Mr. Kamikaze and decided it was not worth my time) and settle on optimal gear set up:
Hunter: level 30 with plasma storm (the omega blaster has higher attack but I found it unreliable and sometimes reflected shots back at me), face guard, Saratoga suit, battle knuckles, clad boots. In the white tank with V100 Kong engine, 200mm Gaia cannon with maxed attack and ammo, thunderstorm with maxed attack, Solomon 2 CPU with maxed hit and evade, mc striker rocket launcher with no upgrades, 204 chassis defense and default extra shells.
Sama the mechanic: level 30 with howling gun for single and hand Vulcan for groups, face guard, medical suit, battle knuckles, clad boots. In the tiger tank with; V100 Kong, 225mm Hydra cannon with maxed attack and ammo, 25mm machine gun with maxed attack, Noah system CPU with maxed hit, ATM red peony with no upgrades, 204 chassis defense and default extra shells.
Ciel: level 30 with the best single target laser bazooka and TNT paranoia for groups, face guard, assault armor, guard knuckles and clad boots. In the red tank with V100 Kong engine, 195mm burst cannon with maxed attack and ammo, 25mm machine gun with maxed attack, emmy CPU with maxed hit and evade, S tornado with no upgrades, 206 chassis defense and default extra shells.
Everyone had gas mask, earplugs, grounding tail on person and electromagnetic barrier, camouflage shield, stealth coat, mirror coat, radar scope, auto ac, grounding chain and alkaline coat on tanks. The towed LAV has a V100 Kong engine, 165mm ghost cannon with maxed ammo, default emmy CPU, and excalibur missile launcher with maxed ammo (for ambush and support roles). Extra shells were a mix of piercing and spare. I did not try out every type of shell.
I wrecked the final boss and did not need those special weapons or extra shells. I loved this game and found the entire setting and vehicle mechanics enthralling. Could have been more story and character development. The game is stellar, especially considering it is a remake of a NES game.