choas axe

where can I buy a max dmg chaos axe and how much would that cost.

buy from other people.if you want one without mods around 500g-1k

are they really that cheap most max dmg weapons are 1500g-2000g

They're a dime a dozen in the Fissure, but they'd probably go for ~1k max from sellers. Your best bet is just taking a trip down there, you're bound to find one.

They're not really a dime a dozen in FoW. Sure, they drop all the time but I only see maybe 1 max damage axe drop each run. And maybe a purple or gold one every 10 runs. In fact, in about 50 FoW runs I have never seen a Gold Chaos Axe

I bought mine for 1k and later sold it for 1.5k because, well, I was a noob and I needed money.
Sold right away, btw.