diff --git a/setup b/setup
index 018891e..a758e08 100755
--- a/setup
+++ b/setup
@@ -2,12 +2,16 @@
 
 . ./vars.sh
 
+if [ ! -d "boxes" ]; then
+    mkdir boxes
+fi
+
 VBoxManage createvm --name ${NAME} --ostype ${TYPE} --register
 
 VBoxManage modifyvm ${NAME} \
     --vram 12 \
     --accelerate3d off \
-    --memory 613 \
+    --memory ${MEMORY_SIZE} \
     --usb off \
     --audio none \
     --boot1 disk --boot2 dvd --boot3 none --boot4 none \
@@ -24,9 +28,9 @@ VBoxManage modifyvm ${NAME} \
     --bioslogodisplaytime 0 \
     --biosbootmenu disabled
 
-VBoxManage createhd --filename "${HDD}" --size 8192
+VBoxManage createhd --filename "${HDD}" --size ${HDD_SIZE}
 # Swap is recommended to be double the size of RAM.
-VBoxManage createhd --filename "${HDD_SWAP}" --size 1226
+VBoxManage createhd --filename "${HDD_SWAP}" --size ${HDD_SWAP_SIZE}
 
 VBoxManage storagectl ${NAME} \
     --name SATA --add sata --portcount 2 --bootable on
diff --git a/vars.sh b/vars.sh
index f8a37af..029ea62 100644
--- a/vars.sh
+++ b/vars.sh
@@ -1,7 +1,10 @@
 NAME=centos65-x86_64
 TYPE=RedHat_64
 INSTALLER="./isos/CentOS-6.5-x86_64-minimal.iso"
-GUESTADDITIONS="./isos/VBoxGuestAdditions-4.3.6.iso"
+GUESTADDITIONS="./isos/VBoxGuestAdditions_4.3.6.iso"
+MEMORY_SIZE=613
 HDD="${HOME}/VirtualBox VMs/${NAME}/main.vdi"
+HDD_SIZE=8192
 HDD_SWAP="${HOME}/VirtualBox VMs/${NAME}/swap.vdi"
+HDD_SWAP_SIZE=$((MEMORY_SIZE*2))
 NATNET=10.0.2.0/24