Half of the fun of Knights of the Old Republic is developing your party members in your own individual way, and I encourage you to do so. Nonetheless, I am providing development guides for every playable character as I have figured out ways to develop a very powerful party, and if you're the type of person, like me, who enjoys a Dungeons & Dragons/Wizards of the Coast -type battle system; then even if you don't follow the guides, they may hopefully at least provide interesting reading and food for thought...
HK-47 is Level 6 when he joins your party.
At Level 6, HK-47 has the following Attributes:
At Level 20, I have HK-47 with the following Attributes:
I then equip the following:
Security Domination Interface - Droid Motion Sensors Type 3 - Security Decryption Interface - (full list of Droid Upgrades here) - Baragwin Shield Disruptor - Baragwin Flame Thrower (Droid Weapons list here) - Composite Heavy Plating (Droid Armor list here). N.B. I take advantage of a glitch to be able to obtain multiple Baragwin items and Composite Heavy Plating, so that I can equip these to both droids in the game. I'll provide more details on the glitch soon.
For HK's main weapon, it's a choice out of either the Baragwin Ion-X Weapon (Fully Upgraded); Jamoh Hogra's Carbine (Fully Upgraded); or Jurgan Kalta's Assault Rifle (Fully Upgraded) (list of every Blaster Rifle).
Click here for lists of Droid equipment in KOTOR.
At Level 6, HK-47 has the following Feats:
Finally, I have these Feats at Level 20:
At Level 6, HK-47 has the following Skills:
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