Max Power and Influence
To quickly max out Power and Influence in Dragon Age Inquisition, do the following: You must first reach Skyhold. Go to the merchant in the Southwest corner of the courtyard (Farris the Representative). Click on Buy/Sell and go to the Other section Purchase whichever of the Influence/Power items that you can afford. DO NOT exit the merchant at this point. Immediately go to Sell and sell the item back to the merchant. Repeat as desired. When you exit the merchant Buy/Sell screen, you will get the accumulated Influence/Power from your "purchases."
Unlimited Amulets of Power for your Inquisitor
To make use of this glitch you must have reached Skyhold and unlocked Crestwood on your map table*. Travel to Crestwood and locate the village. There is a boarded up and locked house there. To gain access to it you must 1)drain the lake and close the fade rift there and 2) have the Deft Hands perk. After entering this house you will find a bag of loot on the floor along with a chest off to the side. Selectively loot the bag. It will have an "amulet of power" for your inquisitor in it along with atleast one other item. Take the "amulet of power" and leave atleast 1 item in the bag. This can be done with the chest off to the side as well. Now you exit Crestwood then return. There is a quick travel point in the village so you don't need to travel far after returning. Go back into the house and selectively loot the bag & chest again. the "amulet of power" has respawned and there are new items in the chest. * This can be done with any chest or loot drop through out the game, but the "amulet of power" requires the above mentioned conditions.
Infinite Chest Loot
It is simple. Don't take all the items from a chest or anything that has inventory in it. Then travel to another area and then when you come back it will have different loot. This is great for finding rare schematics.
Item Duplication + Infinite Skill points + Unlimited Gold
Once you can enter to Skyhold go into Undercroft (the place where you can make you own weapons and armors) and use the Storage Chest. Storage all the items you want to duplicate first (this works only on Weapons, armors, accessories and upgrades. You can't use this method for crafting materials) Once you have all the things you want to duplicate inside, change from "Inventory" to "Storage" and find the specific item you want to duplicate and press "X" and "O" simultaneously. If worked correctly you will have the item in your inventory as well as in the Storage. This works well with all the Amulets, Rings, weapons and more, so, If you have an "Amulet of Power" for any of your Characters, you can duplicate it and have unlimited skill points for that char. This also works wonders for selling those expensive Rings and Amulets you find after killing a boss, so this is great for unlimited Gold.
FOR XBOX 360
Easy cash/Endless crafting materials
First clear out your valuables via selling, turning in research, destroying, etc. Take whatever crafting item you wish to duplicate (I recommend anything from a dragon for cash) and put it into valuables. Go to any shop and go to the sell valuables section. Hit Y and A in quick succession. It will sell all, and bring up the sell how many window if you had more than one. Sell all with that too. Go to the buy back area and you will see DOUBLE what you had available to buy back. Buy it all, double sell as desired. Does not work with herbs.
Infinite Amulets of Power exploit
Go to Crestwood to the house (village) with the locked door (you need require fine tools and deft hands perk) open chest and ONLY take the amulet. Reload the map(go somewhere else and come back) to refill. As long as you don't take the other item or hit "Take All" the Amulet of Power will be there.
FOR XBOX ONE
Unlimited Ability Points
In any chest that has an Amulet of Power, take only the Amulet of Power. Then travel to another region. Return to the region and the chest for another Amulet of Power. They are character-specific and when equipped grant ability points. You can pick up as many as you like, since they will always appear in the chest.