Stout Shield= Purchase if you think you will take a lot of physical harassment
Quelling Blade= If you think your lane won't take a lot of harassment
Tango= If the enemy plays aggressively in general
Healing Salve= If the enemy lane has a high kill potential lane
Slippers of Agility= For bonus stats and to be crafted into the Poor Man's Shield
Iron Branch= For bonus stats
Poor Man's Shield= For extra early game survivability
Magic Stick= If the enemy heroes spam their abilities a lot
Magic Wand= For team fight survivability
Hand of Midas= If you're the main carry so you can get extra farm (get really early on)
Mask of Madness= For EARLY GAME DPS
Power Treads= Only good boots to boost your DPS further
Diffuse blade can be picked up instead of Hand of Midas if you wish to go for early kills.
Drum of Endurance can be picked up for early game killing potential and a small survivability increase.
Mjollnir= For extra DPS as it works well with your bash and also extra AOE damage
Daedalus= For quicker target take down
Divine Rapier= If this is your last hope of winning
MKB= Against evasion
Butterfly= For extra survivability (not highly recommended)
Desolator= Against low armoured heroes
Vlads= It can become really useful in the LATE GAME due to its 15% bonus damage and life steal, as well as a helpful aura for your team mates to take down targets quicker
Assault Cuirass= This item brings some DPS for Faceless Void however not enough to be an offensive item. Get this if your fearful of physical damage and to boost your team's attack speed in a team fight
Aghanim's Scepter= It's an under rated item for faceless void. With this item you can use your ultimate every 60 seconds and the duration of it increases. Get this if you're not the main carry or if you find yourself having a lot of team fights
BKB= I wouldn't recommend this item unless you find your self being stunned a lot inside your ChronoSphere or hard to hit powerful nukes are always targeting you
Battlefury= Battlefury just doesn't provide enough DPS that Faceless void wants. The cleave is the only thing that makes it an option for Faceless Void, however cleaving your targets isn't as important as killing an important heroes faster. Your team should take care of the other heroes while you destroy the more important ones. And even in the early game the battle fury is useless, however if you purchased mjollnir your chances of getting a kill is much higher.
Satanic= Just don't. You have enough escape mechanisms and a great initiation which makes it that Satanic is pretty much a useless item.
Manta Style= Great with diffusal blade and useful against other hard carries when your ultimate is on cooldown. However, apart from that it's a useless item.
Shadow Blade= The DPS is suitable for faceless void to pick and can help in landing your ultimate, however it is useless otherwise