From Dragon of Desire:

With the sheer amount of Cyberware that you can get, I recommend doubling the Essence stat in the Cyberware config. Even with it doubled it still isn't enough for everything, but at least them you can get more than just the essentials. Hell, a constructed (Not salvaged) cybernetic limb costs 20! that means you could have three cybernetic limbs before going into the danger zone.