Just wanted to share that this trophy is a lot easier to unlock on the First Strike DLC pack (the Ascension-map). There are only 11 wall purchases that need to happen for you to qualify to get this trophy. First, let me say that you need at least around 8,000 points to open the complete map up (without opening the doors that aren't needed). Below, I'll list all the weapons and how to get there.- Olympia (500 points)
On the top level, next to a window.- M14 (500 points)
At the bottom where you came down with the lander.- MPL (1,000 points)
Open the door (750 points) next to the Quick Revive machine in spawn and you will see it right in front of you.- PM63 (1,000 points)
Go through the door next to Quick Revive and go up the stairs. It will be on the wall close to the Juggernog perk machine.- MP5K (1,000 points)
Open the door (750 points) at spawn on the top level and to the right. At the back, you'll see this weapon next to another door you can open for 1,250 points.- M67 Grenades (250 points)
On the opposite side from the MP5K, go up the stairs to see them on the left hand side wall.- AK47u (1,200 points)
After opening the door at the top level on spawn, go to the left and open the gate (1,000 points). You'll see this weapon right in front of you after walking down the path for a little while.- Claymores (1,000 points)
After buying the AK47u, open the door directly on your right to see them on the wall- Stakeout (1,500 points)
Open the door (1,250 points) next to the MP5K and go inside the building. Move up the first stairset to see it in front of you.- M16 (1,200 points)
After opening the door next to the MP5K, move straight forward to open another gate (1,250 points). On your right, you will see a stairset. Next to the Speed Cola-perk, you'll see another staircase. This weapon is at the top.- Sickle (3,000 points)
Buy the door (1,250) points next to the M16 and move towards the lander spawn. You should see it on your right at the far end.
In total, you will need 14,150 points to make all purchases and they can be bought at any point in the game. Just make sure you buy every single item once in a single game. If you need any help, don't hesitate to contact me.
Stay safe and awesome!