I just test with shorting VXX, it looks like it is around 125% UVXY around 180%, with around 10% annual borrowing interest rate ...that is a lot...especially how to practically short UVXY lol
I only know much harder to find shares to short and generally much more expensive with other brokers.
You should avoid holding any VIX related instruments overnight, so your borrowing costs for a short are a non-issue. Also, be aware that IB is quite restrictive on margin issues for these ETFs/ETNs. You need to speak with them directly. If you need leverage, you may want to look at options on VXX. They trade very tight spreads. Good luck.
I dont think you can shorty UVXY anywhere right now. But why not just do it with futures? And at the old, -2 ratio? No one seems to be talking about it, but UVXY isn;t just comprised of the futures positions of late, but includes some swap in it. To me this is a red flag, and I'd keep the hell away from the thing for the time being. I watch what belies it i terms of holding each day, and this, though permitted in the prospectus, to me has my antenna humming.
IB let you short UVXY for sure, I already show the rate. I think people buy/sell vix etf for these reasons: 1. vix future is damn expensive, people can play with VXX/UVXY with much less money 2. buy/sell price bid range is wider for vix future, bad for day trade 3. you can long/short vxx/uvxy for years without touching it, future you need to manually move it month by month. The bad factor of short vix etf is that...stuff like XIV would be busted with a well designed plan like last time.