On FV you can save yourself a lot of time and skip certain achievments by buying the end result in bazaar or borrowing from a friend.
As a general rule of thumb, when you look at an achievement, any steps that are slightly indented are "optional" steps and do not need to be completed.
For an example, look at the Valthun's Memory Shard achievement in the conquest tab, the step "Obtain Valthun's memory shard" is not indented which means it's a mandatory step; however, the 5 lines below "Obtain Valthun's memory shard" are all indented , so these are optional steps. By getting the Valthun's memory shard augment from someone who already has one, you will satisfy the only mandatory step in this achievement and be granted the achievmeent without doing any tasks.
Now compare this with the "cursed Obsidian Faycite" achievmeent in the conquest tab. None of the steps in this achievement are indented, so you need to complete all the tasks even if you buy a Cursed Obsidian Faycite aug (which is tradable) in the bazaar.
With that in mind, here are some tradable items you can buy on FV that will grant achievements right away and allow you to skip these portions of the hero's journey:
-Wayfarers Brotherhood Emblem (HUGE time saver if you get this from someone. Skips doing any LDON missions)
-tome of new beginnings
-assistant researcher's symbol
-tsaph katta's urn of rejuvenation
-valthun's memory shard
-lantern o'wisps
-shield of the otherworld
you can also buy jonas digmire's skeletal hand and get that achievment; however, the tasks for this aug are also needed for other achievements, so you don't really save any time in the end. Meanwhile something like shield of the otherworld is used in 2 achievements but you don't need to do any of the actual tasks since having the aug will give credit for both.
Edited, Jan 25th 2015 1:04pm by NewbishTroll