1. Determine what skill to use:
A. Finding Items: Commerce vs. Inquiry
Commerce is the basic skill and represets finding things through legit trade routes, depots etc.
Inquiry is often used for illicit goods and things not readily available. Black markets etc.
The GM will decide based on the item whether one skill or the other is the primary route on a per item basis.
Roll the primary skill, and if both are applicable, then the secondary skill can be used to add a
+1% bonus per success level to the primary roll.
B. Price: Commerce vs. Barter
Commerce leverages knowledge of rarity and availability to adjust the price based on prevailing market conditions.
Barter relies on individual dealings and may not be applicable. (See barter skill description).
Only one of the two skills should be rolled to adjust price.

Step 2. Commerce and/or Inquiry test to see if it is at all available for purchase.
It must be successful based on the population and avail.
Level of success can allow the time metric to be reduced by 1 step per 10% success level.
This will usually take a day worth of shopping. Though several items can be inquired about at each planet.
Generally 1 item for every 10 points of Fellowship at least 1. Round off.

Step 3. Commerce or Barter to see what price it can be gotten at. Success indicates that it can be acquired at it's normal cost. Every full 10% failure level +50% the cost at which it can be acquired. (Actual math multiplier of +5% cost per point failed).
Commerce test of BETTER than 10% reduces the cost by 1% per 1% better than 20% success.
Max of 10% of base cost of the item. (This can either be amazing avail, or the vendor just doesnt know what he has)
Modifiers:
Avail track:
Ubiquitous : +30
Abundant : +20
Plentiful : +10
Common : 0
Average : -10
Scarce : -20
Rare : -30
Very Rare : -40
Extremely Rare : -50
Near Unique : -60
Unique : -70

Population:
<1k1k-10k10k-100k100k+
0+10+20+30

Craftsmanship availability modifier:
BestGoodCommonPoor
-20-100+10

Time Metric by pop <10k:
Ubiquitous : 1 day
Abundant : 1d5 days
Plentiful : 1d10 days
Common : 1d10 days
Average : 1 week
Scarce : 2 weeks
Rare : 1d5 weeks
Very Rare : 1d10 weeks
Extremely Rare : 1d5 months
Near Unique : 1d10 months
Unique : 1 year

- 1 chart on time at 10k, 100k, 1M, 10M+

-1 chart on time per success above 1 achieved

Since this can bring the chart to below the baseline:
0 : Ubiquitous : 1 day
-1 : 1d10 hours
-2 : 1 hour
-3 : 30 minutes
-4 : 15 minutes
-5 : 10 minutes
-6 : 5 minutes
-7 or more : Look what I have under the counter!

Time metric:
Best Good Common Poor
X3 X2 - X1/2

Finally Quality modifier on cost:
Best Good Common Poor
X10 X3 X1 X1/2