I'm using a lot of trouble finding information on filing taxes when trading forex using an international broker (outside the US). Most info seems to come from only 1 source, Greentradertax; difficulty is they don't do taxes or offer much advice for foreign accounts / brokers.
When I started trading a year ago I thought most folks used broker accounts outside the US... Guess I was wrong.

Anyway I had a massive loss in 2017 and I'm wondering if it's worthwhile to write them off on taxes under sec 988. Has anyone here written a forex loss off based on their non US broker account? Was the resulting audit a very simple verifiion of documents and also fund transfers or did you need expensive lawyers? In my simpleton comprehension one shouldn't need lawyers unless there's fraud or evasion, but these conditions I envision are subject to irs interpretation considering there's always a plethora of too complex laws we don't even know exist. Additionally wondering exactly what form to write off sign supplier fees, since they'd most likely be different than where inventory commissions are lined. Anyone know great accountants that do foreign brokers?