Hi there,
It is possible to get into a brick uni by studying OU courses, but this would totally depend on which uni and what you want to study there: if you know which unis you want to apply to, your best bet is to call or email their admissions people and ask if they'd accept OU points for entry onto whatever course it is you want to apply for, and, if so, how many points, at what level and in which subject(s). There's no hard and fast answer because this would be a non-standard way to enter a brick uni, sorry!
As for finance with the OU, you apply on a per course rather than per qualification basis.