SWTOR Crafting Supplement Costs

In SWTOR (Star Wars The Old Republic), most crafting schematics require Supplements to make basic building block components (Assemblies, Bonded Attachments, and Cell Grafts). You can get these supplements in three main ways: From Crew Skill Missions (Archaeology, Bioanalysis, or Scavenging), the Crew Skill Vendor, and the Galactic Trade Network. Here is a chart with the comparative costs.
Remember that Free-to-Play and Preferred players buy from the Crew Skill Vendor at 125% normal price.

• Vendor - Remember that Free-to-Play and Preferred players buy from the Crew Skill Vendor at 125% normal price (rounded down).
• Mission Cost - This is the cost of a Crew Skill Mission to get the Crafting Supplement. There is a slight chance of total failure, resulting in no materials and no credit refund.
• Mission (5) - This is the cost-per-unit if the Crew Skill Mission returns the minimum number of units, which is 5 units. Typically a mission returns 5-10 units, or about three times that much on a critical success.
• Mission (7) - This is the cost-per-unit if the Crew Skill Mission returns the average of 7 units.
• Mission (10) - Assuming that 1 in 4 missions is a critical success (25% from Companion Influence level 50), on average you will get 10 units per mission.

Grade	Vendor	Mission Cost	Mission (5)	Mission (7)	Mission (10)
1	10	125	25	18	13
2	50	525	105	75	53
3	100	925	185	132	93
4	150	1300	260	186	130
5	200	1600	320	229	160
6	400	1850	370	264	185
7	600	2100	420	300	210
8	800	2350	470	336	235
9	1200	2600	520	371	260
10	1800	2850	570	407	285

You can see that you are most likely to get your credits' worth if you run Crew Skill Missions for Grade 6+ Crafting Supplements, and you are better off saving time (and often credits) to buy Grade 1-5 Supplements from the Vendor.

However, an additional consideration for Grade 6 Crafting Supplements is running Slicing Grade 9 Lockbox missions instead since you might net just as much in versatile credits.

Therefore, our final recommendation is to run Crew Skill Missions (especially if you are using high-Influence companions) for Grades 7 to 10, and buy Grades 1-6 either from the Crew Skill Vendor or from the Galactic Trade Network where deals might show up at below-Vendor prices.