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Skyrim Perks Ancillary- Speechcraft
http://www.rarityguide.com/articles/articles/4297/1/Skyrim-Perks-Ancillary--Speechcraft/Page1.html
By Nick M. Facer
Published on 02/13/2013
 
The Speechcraft perk tree has two branches- one for those of a more buy/sell/trade bent, and the other for those who like to engage in more... dubious business practices.  The latter branch is sadly less useful in most cases, particularly for the skullduggerists who are part of the Thieves' Guild anyways...

Haggling-

If you ever find yourself short of gold you wish you had this skill.  While the first rank is better than the subsequent ranks, it’s not by much- especially given that later on in the game adding 5% to each transaction you make becomes a bigger and bigger deal as you deal in more and more valuable items.  Even if you’re not investing in Speechcraft perks, you really should have the first rank of this, it’ll make your way through the land of Skyrim that much less destitute.

Allure-

This is really only going to be noticeable if you take the time to locate merchants of the right gender for what you want to sell or buy (more likely buy, once you’ve got the Merchant perk).  Otherwise, it’ll still help, but not enough to be worth the perk point.  So make sure you keep track of your own gender as well (this can be difficult if you play in first-person mode all the time) and match your choice of shops accordingly.

Bribery-

This can actually get a bit expensive- each time you bribe a guard only works for the time being.  It won’t ever clear you of bounty or crimes, it just persuades someone to look the other way.  This really doesn’t mean anything if you follow the laws to begin with, nor is it going to help you in the event that you’re already part of the Thieves’ Guild and thus can do the same thing for free.

Merchant-

This is actually a very valuable perk, cutting a lot of your visits to town down to a single stop and reducing the amount of wandering around the city looking for the odds-and-ends shop you do each time you go anywhere.  If time is a concern to you, this is well worth the perk point.  If you don’t mind, don’t care, or would be visiting all the shops anyways, you probably shouldn’t worry about this, though.

Persuasion-

Useful for turning the story in the direction you want or completing a surprisingly wide variety of quests, this perk is rarely necessary but frequently helpful.