OP, after you verified your account and got your money out, ask them to delete your KYC data. I've read that especially if you're from europe (EU), they probably will have to adhere your request (due to GPDR (?)).
Not that i'd verify the account for 150$ in the first place, because really, Bittrex and Poloniex are untrustworthy in my book.
Is that even possible? Will they really delete my data? I live in the South East Asia.
You'll have to decide whether or not it is worth it for you, but I wouldn't be sending my documents to a faceless stranger at a company with unknown security practices for $150.
I'm really planning to complete identity verification because I really need some money now. But if they ask more documents other than what they want on verification procedure then I won't continue.