Updated Mercantile plugin to add new "Global Variables", for people who want to tweak the rates.
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From Read-Me:
NOTE: USERS OF "PROGRESS" SHOULD KNOW THAT THIS MOD TRIES TO TAKE MERCANTILE PROGRESSION IN HAND AND RAISE IT MANUALLY, BUT "PROGRESS" RESTORES THE MERCANTILE PROGRESSION TO THE OBLIVION ENGINE, SO YOU WOULD HAVE A COMBINED PROGRESSION OF MERCANTILE AND IT WOULD RISE ALMOST TWICE AS FAST.
SOLUTION: YOU SHOULD LOWER THE RATE OF MERCANTILE PROGRESSION IN "PROGRESS" TO ZERO, OR NEAR IT.
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For each level of mercantile you have to exchange a sum of money to be able to advance to the next level, and the amount of money you need to exchange is calculated by the following formula:
Set tmp to Player.GetBaseActorValue Mercantile Set Exchange to ( spMerC2 * tmp * tmp ) + ( spMerC1 * tmp ) + spMerC0
Where [spMerC0=30], [spMerC1=12] and [spMerC2=0.45], by default. Example amounts are below:
Mer[20]: Exchange money = 180 + 240 + 30 = 450Mer[40]: Exchange money = 720 + 480 + 30 = 1230Mer[60]: Exchange money = 1620 + 720 + 30 = 2370Mer[80]: Exchange money = 2880 + 960 + 30 = 3870
So if your mercantile is 60 you need to sell 2370 Septims worth of loot to the vendors in order to advance in mercantile.
Or you have to buy spells and items totally worth 2370/0.2=11850 Septims.
Remember if you buy a house or horse, their price is calculated as well.
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There are some "Global Variables" that affect the Mercantile skill progression, and you can change them if you know what you are doing.
Variable = Default value; Syntax
Mercantile cap: If you use Elys Uncapper you can raise it, or you can limit yourself and lower it.
spMerCap = 100
Formula coefficients: You can play with them, but be wary, as this is an exponential formula.
spMerC0 = 30.0; Constant spMerC1 = 12.0; Linear spMerC2 = 0.45; Exponential
Effect of buying and selling on Mercantile progression: Lower them for harder setting.
spMerRatioBuy = 0.2 spMerRatioSell = 1.0
Note: if you lower the Buy and Sell ratios, it would take more gold to raise your Mercantile skill.
Download it http://tesnexus.com/downloads/file.php?id=13677.