Quote from atticus:
lol wrong.
My brother had an account with $0.00 that he just put $500 in via ACH for quote access and it is open to trade. The account had been closed for a year. He had to reaffirm those suitability questions, but he ACH'd $500. He even bought a calendar spread with the $500.
IOW, you need at least $500 to sub to quotes, but that's it.