Increase Cash (Bug Exploitation):

Just before completing the mission, do a save or quicksave. Complete the mission and save it in a different save slot. Reload your last save or quicksave before completing the mission. Complete the mission again. The statistics screen should now have ADDED TOGETHER the loot from BOTH mission completions. Apparently, the variable which stores treasure amount at the end of the mission is not being cleared between loads. You can keep doing this until you have all the cash you need to buy out the store at the loadout screen for the mission immediately following.

Modify Starting Cash:

You can edit the dark.cfg file and add the line "cash_bonus n" N represents the amount of cash added to the beginning of a mission.

Skip to Next Mission:

Press [CTRL] + [ALT] + [SHIFT] + [END] to skip to the next mission.

Hints:

The security cameras can be shut off one of two ways: find the switch or use a fire arrow.

Guards who come across the unconscious or dead bodies of their compatriots will sound the alarm. Be sure to stuff the bodies in out-of-the-way places. Bodies of water (pools, streams) work very well.

If you must fight with the sword, use short, choppy strokes. Hitting a guard will often break his swing.

Pick up everything you can get your hands on. You'll always be able to use the extra cash