I’m sorry to say my knowledge is limited on the Regents selection process since, as I’m sure you’ve already realized, there really isn’t much out there. The number selected tends to hover around 200 scholars chosen per year for Berkeley. As a freshman there is an interview process, but there are other people much more knowledgeable on what that is like than I am. The numbers on how many students are invited is much less clear, but most sources say that about 2% end up getting the invitation. Anyway, Berkeley and UCLA are distinct from the other UCs in that they have another application process for the regents scholarship, while the others make selections exclusively based on the UC application. There are also some slight differences in the award amount, but it’s generally somewhere around $2500 per year.