There are 6 Weapons that have 3 Levels each that need to be purchased. You will need roughly about 100,000 Tech Points to Upgrade everything. This will be the very last Achievement you will unlock in this game. The best place to get EASY Tech Points is on Chapter 2-4 Breaking Point - On Casual - When the mission starts look up and get into a turret and destroy all the UFO's. Once you do that and get a cut-scene, go to the 3 different yellow markers and kill all the enemies. Once you are told to go to the yellow marker to retrieve the weapon DO NOT! Instead go and find another turret and hop in and destroy all the UFO's. There are about 50-60 in all. Once they are all destroyed get out and you retrieve the weapon, Charge the 4 objects and then destroy the 4 gates. Once you do this you will get a checkpoint. You can now quit and replay the chapter and all your money WILL be saved! Each run will net you around 7000 TECH points.