P/C Red Katana 14 STR, 112 W. Att, 4 W. Def, 0 Slots

I am not looking to sell this at this moment, as I just hit level 70 and will be using this for my foreseeable future until level 150 or so, I'd imagine. I am merely looking for honest price checks on the value of this item. So far in game I've seen the whole rainbow...

Some have offered me 200m, Others say its valued at about 500m, friends have said it can go for 1b.

If you have any comparables that have sold or that you've bought recently, please share with me three pieces of information about the transaction:

1. The stats of the Red Katana exchanged
2. The price sold/bought for
3. The rough timeline of when the transaction took place

Thank you in advance! ^^