If you know how to dupe then you will need to do it.

Step 1: Equipment needed is at least 200 of one type of scroll (I used Absorb Minor Magicka). You go the the Bookshop in the Imperial City. You get a book called The Waters of Oblivion (if you already have over 6,600 then you can skip this next step).

Step 2: Dupe the books with your 200 scrolls and sell them to the manager of the store. Then you should have over 6,600 and if you dont then do this step all over again until you have the exact money or more.

Step 3: Buy Document of Purile Banter and dupe it also and pick them up and sell them to him. You need to keep at least one copy if you want to do it again.

I did this and got over 200,000 in just an hour!