In our case, we allow up to 30 x your equity as long as you're relatively hedged ( $500K long, $490K short for example).
You are allowed 6 times your equity with no "haircut" fees. 2% per Year for balances between 6 and 10 times equity, thus less than 1% per Year for carrying 10 times overnight.
No haircut fees for intraday balances.
IMO, to be successful as a pairs trader, you must have the ability to carry positions for days or weeks.... the "pure" daytrader is adapting to this need lately as well.
FWIW guys!!
Don